UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D. C. 20549

FORM 10-K

(Mark One)

[X] Annual Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the fiscal year ended December 31, 2018

[ ] Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

For the transition period from to

Commission file number 1-11294

Unum Group

(Exact name of registrant as specified in its charter)

Delaware	62-1598430
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
1 FOUNTAIN SQUARE CHATTANOOGA, TENNESSEE	37402
(Address of principal executive offices)	(Zip Code)
423.294.1011
(Registrant's telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Name of each exchange on which registered
Common stock, $0.10 par value	New York Stock Exchange

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer as defined in Rule 405 of the Securities Act. Yes [X] No [ ]

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes [ ] No [X]

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. [ ]

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act.

(Check one):

Large accelerated filer	x	Accelerated filer	¨
Non-accelerated filer	¨	Smaller reporting company	¨
		Emerging growth company	¨
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.			¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes [ ] No [X]

The aggregate market value of the shares of the registrant's common stock held by non-affiliates (based upon the closing price of these shares on the New York Stock Exchange) as of the last business day of the registrant's most recently completed second fiscal quarter was $8.1 billion. As of February 15, 2019, there were 214,625,710 shares of the registrant's common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the information required by Part III of this Form 10-K are incorporated herein by reference from the registrant's definitive proxy statement for its 2019 Annual Meeting of Stockholders which will be filed with the Securities and Exchange Commission pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended, within 120 days after the end of the registrant's fiscal year ended December 31, 2018.

TABLE OF CONTENTS

		Page
	Cautionary Statement Regarding Forward-Looking Statements	1
	PART I
Item 1.	Business	2
Item 1A.	Risk Factors	19
Item 1B.	Unresolved Staff Comments	30
Item 2.	Properties	30
Item 3.	Legal Proceedings	30
Item 4.	Mine Safety Disclosures	30
	PART II
Item 5.	Market for the Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities	31
Item 6.	Selected Financial Data	32
Item 7.	Management's Discussion and Analysis of Financial Condition and Results of Operations	34
Item 7A.	Quantitative and Qualitative Disclosures About Market Risk	90
Item 8.	Financial Statements and Supplementary Data	97
Item 9.	Changes in and Disagreements with Accountants on Accounting and Financial Disclosure	190
Item 9A.	Controls and Procedures	190
Item 9B.	Other Information	192
	PART III
Item 10.	Directors, Executive Officers and Corporate Governance	193
Item 11.	Executive Compensation	193
Item 12.	Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters	194
Item 13.	Certain Relationships and Related Transactions and Director Independence	195
Item 14.	Principal Accounting Fees and Services	195
	PART IV
Item 15.	Exhibits and Financial Statement Schedules	196
	Index to Exhibits	207
	Signatures	211

Cautionary Statement Regarding Forward-Looking Statements

The Private Securities Litigation Reform Act of 1995 (the Act) provides a "safe harbor" to encourage companies to provide prospective information, as long as those statements are identified as forward-looking and are accompanied by meaningful cautionary statements identifying important factors that could cause actual results to differ materially from those included in the forward-looking statements. Certain information contained in this Annual Report on Form 10-K (including certain statements in the business description in Item 1, Management's Discussion and Analysis in Item 7, and the consolidated financial statements and related notes in Item 8), or in any other written or oral statements made by us in communications with the financial community or contained in documents filed with the Securities and Exchange Commission, may be considered forward-looking statements within the meaning of the Act. Forward-looking statements are those not based on historical information, but rather relate to our outlook, future operations, strategies, financial results, or other developments. Forward-looking statements speak only as of the date made. We undertake no obligation to update these statements, even if made available on our website or otherwise. These statements may be made directly in this document or may be made part of this document by reference to other documents filed by us with the Securities and Exchange Commission, a practice which is known as "incorporation by reference." You can find many of these statements by looking for words such as "will," "may," "should," "could," "believes," "expects," "anticipates," "estimates," "plans," "assumes," "intends," "projects," "goals,” "objectives," or similar expressions in this document or in documents incorporated herein.

These forward-looking statements are subject to numerous assumptions, risks, and uncertainties, many of which are beyond our control. We caution readers that the following factors, in addition to other factors mentioned from time to time, may cause actual results to differ materially from those contemplated by the forward-looking statements:

• Sustained periods of low interest rates.

• Fluctuation in insurance reserve liabilities and claim payments due to changes in claim incidence, recovery rates, mortality and morbidity rates, and policy benefit offsets due to, among other factors, the rate of unemployment and consumer confidence, the emergence of new diseases, epidemics, or pandemics, new trends and developments in medical treatments, the effectiveness of our claims operational processes, and changes in governmental programs.

• Unfavorable economic or business conditions, both domestic and foreign, that may result in decreases in sales, premiums, or persistency, as well as unfavorable claims activity.

• Changes in or interpretations of laws and regulations, including tax laws and regulations.

• A cyber attack or other security breach could result in the unauthorized acquisition of confidential data.

• The failure of our business recovery and incident management processes to resume our business operations in the event of a natural catastrophe, cyber attack, or other event.

• Investment results, including, but not limited to, changes in interest rates, defaults, changes in credit spreads, impairments, and the lack of appropriate investments in the market which can be acquired to match our liabilities.

• Increased competition from other insurers and financial services companies due to industry consolidation, new entrants to our markets, or other factors.

• Changes in our financial strength and credit ratings.

• Our ability to execute on our technology systems upgrades or replacements.

• Damage to our reputation due to, among other factors, regulatory investigations, legal proceedings, external events, and/or inadequate or failed internal controls and procedures.

• Actual experience in the broad array of our products that deviates from our assumptions used in pricing, underwriting, and reserving.

• Changes in accounting standards, practices, or policies.

• Effectiveness of our risk management program.

• Contingencies and the level and results of litigation.

• Availability of reinsurance in the market and the ability of our reinsurers to meet their obligations to us.

• Ineffectiveness of our derivatives hedging programs due to changes in the economic environment, counterparty risk, ratings downgrades, capital market volatility, changes in interest rates, and/or regulation.

• Fluctuation in foreign currency exchange rates.

• Ability to generate sufficient internal liquidity and/or obtain external financing.

• Recoverability and/or realization of the carrying value of our intangible assets, long-lived assets, and deferred tax assets.

• Terrorism, both within the U.S. and abroad, ongoing military actions, and heightened security measures in response to these types of threats.

All subsequent written and oral forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section.

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PART I

ITEM 1. BUSINESS

General

Unum Group, a Delaware general business corporation, and its insurance and non-insurance subsidiaries, which collectively with Unum Group we refer to as the Company, operate in the United States, the United Kingdom, Poland, and, to a limited extent, in certain other countries. The principal operating subsidiaries in the United States are Unum Life Insurance Company of America (Unum America), Provident Life and Accident Insurance Company (Provident), The Paul Revere Life Insurance Company (Paul Revere Life), Colonial Life & Accident Insurance Company, Starmount Life Insurance Company (Starmount Life), in the United Kingdom, Unum Limited, and in Poland, Unum Zycie TUiR S.A. (Unum Poland). We are a leading provider of financial protection benefits in the United States and the United Kingdom. Our products include disability, life, accident, critical illness, dental and vision, and other related services. We market our products primarily through the workplace.

We have three principal operating business segments: Unum US, Unum International, and Colonial Life. Our other segments are the Closed Block and Corporate segments. These segments are discussed more fully under "Reporting Segments" included herein in this Item 1.

Business Strategies

The benefits we provide help protect people from the financial hardship of illness, injury, or loss of life by providing support when it is needed most. As one of the leading providers of employee benefits in the U.S. and the U.K., we offer a broad portfolio of products and services through the workplace.

Specifically, we offer group, individual, and voluntary benefits, either as stand-alone products or combined with other coverages, that help employers of all sizes attract and retain a stronger workforce while protecting the incomes and livelihood of their employees. We believe employer-sponsored benefits represent the single most effective way to provide workers with access to the information and options they need to protect their financial stability. Working people and their families, particularly those at lower and middle incomes, are perhaps the most vulnerable in today's economy yet are often overlooked by many providers of financial services and products. For many of these people, employer-sponsored benefits are the primary defense against the potentially catastrophic fallout of death, illness, or injury.

We have established a corporate culture consistent with the social values our products provide. We are committed not only to meeting the needs of our customers who depend on us, but also to operating with integrity and being accountable for our actions. Our sound and consistent business practices, strong internal compliance program, and comprehensive risk management strategy enable us to operate efficiently as well as to identify and address potential areas of risk in our business. We have also applied these same values to our social responsibility efforts. Because we see important links between the obligations we have to all of our stakeholders, we place a strong emphasis on contributing to positive change in our communities.

We believe our disciplined approach to providing financial protection products at the workplace puts us in a position of strength as we seek to capitalize on the growing and largely unfilled need for our products and services. We protect people when they need it most, and we believe the need for our products and services remains strong. We intend to continue protecting our solid margins and returns through our pricing and risk actions. We also continue to invest in our infrastructure and our employees, with a focus on quality and simplification of processes and offerings. Our strategy is centered on market growth through the expansion of our product portfolio, distribution system, and geographic footprint, and enhancing the customer experience through efficiency, simplification, and investment in digital capabilities. Accordingly, we continue to identify ways to expand our product offerings, which we believe will allow us to strengthen our brand through both new and existing customer relationships. Although the low interest rate environment continues to place pressure on our profit margins, we continue to analyze and employ strategies that we believe will help us navigate this environment and allow us to maintain solid operating margins and significant financial flexibility to support the needs of our businesses, while also continuing to return capital to our shareholders and exploring merger and acquisition opportunities to enhance our business lines. We have substantial leverage to rising interest rates and an improving economy which generates payroll growth and wage inflation. We believe that consistent operating results, combined with the implementation of strategic initiatives and the effective deployment of capital, will allow us to meet our long-term financial objectives.

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Reporting Segments

Our reporting segments are comprised of the following: Unum US, Unum International, Colonial Life, Closed Block, and Corporate. In connection with our acquisition of Unum Poland in the fourth quarter of 2018, we changed the name of our Unum UK segment to Unum International. The Unum International segment is comprised of our Unum UK line of business and our Unum Poland line of business. The percentage of consolidated premium income generated by each reporting segment for the year ended December 31, 2018 is as follows:

Unum US	63.8	%
Unum International	6.3
Colonial Life	17.9
Closed Block	12.0
Total	100.0	%

Financial information, including discussion of the acquisition of Unum Poland, is provided in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 and Note 13 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Unum US Segment

Our Unum US segment includes group long-term and short-term disability insurance, group life and accidental death and dismemberment products, and supplemental and voluntary lines of business. The supplemental and voluntary lines of business are comprised of individual disability, voluntary benefits, and dental and vision products. Unum US products are issued primarily by Unum America, Provident, and Starmount Life. Paul Revere Life previously issued products reported in our Unum US segment and continues to service the in-force policies, but Paul Revere Life no longer actively markets new business. These products are marketed through our field sales personnel who work in conjunction with independent brokers and consultants. Our market strategy for Unum US is to effectively deliver an integrated offering of employee benefit products in the group core market segment, which we define for Unum US as employee groups with fewer than 2,000 employees, the group large case market segment, and the supplemental and voluntary market segment.

The percentage of Unum US segment premium income generated by each product line during 2018 is as follows:

Group Disability	43.1	%
Group Life and Accidental Death & Dismemberment	30.3
Individual Disability	7.4
Voluntary Benefits	15.6
Dental and Vision	3.6
Total	100.0	%

Group Long-term and Short-term Disability

We sell group long-term and short-term disability products to employers for the benefit of employees. Group long-term disability provides employees with insurance coverage for loss of income in the event of extended work absences due to sickness or injury. We offer services to employers and insureds to encourage and facilitate rehabilitation, retraining, and re-employment. Most policies begin providing benefits following 90 or 180 day waiting periods and continue providing benefits until the employee reaches a certain age, generally between 65 and 70, or recovers from the disability. The benefits are limited to specified maximums as a percentage of income. Effective January 1, 2018, coverage began for our new medical stop-loss product, which is included in our group long-term disability product line. Medical stop-loss is designed to protect self-insured employers if their employees' medical claims exceed certain agreed upon thresholds.

Group short-term disability insurance generally provides coverage from loss of income due to injury or sickness, effective immediately for accidents and after one week for sickness, for up to 26 weeks, limited to specified maximums as a percentage of income.

Premiums for group long-term and short-term disability are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. In some cases, coverage for large employers will

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include retrospective experience rating provisions or will be underwritten on an experience-rated basis. Premiums for experience-rated group long-term and short-term disability business are based on the expected experience of the client given its demographics, industry group, and location, adjusted for the credibility of the specific claim experience of the client. Both group long-term and short-term disability are sold primarily on a basis permitting periodic repricing to address the underlying claims experience. We also offer fee-based administrative services only (ASO) products, where the responsibility for funding claim payments remains with the customer, and fee-based family medical leave products. Premiums for our medical stop-loss product are generally based on the number of covered employees in self-insured employer groups and their estimated overall health risk plus provisions for administrative expenses, and profit.

We have defined underwriting practices and procedures. If the coverage amount exceeds certain prescribed age and amount limits, we may require a prospective insured to submit evidence of insurability. Our disability policies are typically issued, both at inception and renewal, with rate guarantees. For new group policyholders, the usual rate guarantee is one to three years. For group policies being renewed, the rate guarantee is generally one year, but may be longer. The profitability of the policy depends on the adequacy of the rate during the rate guarantee period. The contracts provide for certain circumstances in which the rate guarantees can be overridden. Our medical stop loss contracts are typically renewable on an annual basis and rates are not guaranteed beyond one year. There is no requirement for prospective insureds to submit evidence of insurability because coverage levels are determined for the group as a whole.

Profitability of group long-term and short-term disability insurance and our medical stop-loss product is affected by sales, persistency, investment returns, claims experience, and the level of administrative expenses. Morbidity is an important factor in disability claims experience, and many economic and societal factors can affect claim incidence for disability insurance. We routinely make pricing adjustments on our group insurance products, when contractually permitted, which take into account emerging experience and external factors.

Group Life and Accidental Death and Dismemberment

Group life and accidental death and dismemberment products are sold to employers as employee benefit products. Group life consists primarily of renewable term life insurance with the coverages frequently linked to employees' wages and includes a provision for waiver of premium, if disabled. Accidental death and dismemberment consists primarily of an additional benefit amount payable if death or severe injury is attributable to an accident.

Premiums are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting practices and rate guarantees are similar to those used for group disability products, and evidence of insurability is required for benefits in excess of a specified limit.

Profitability of group life and accidental death and dismemberment insurance is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Individual Disability

Individual disability products are offered primarily to multi-life employer groups to supplement their group disability plans and may be funded by the employer, but the policy is owned by the employee and is portable. Individual disability insurance provides the insured with a portion of earned income lost as a result of sickness or injury. The benefits, including the underlying group disability coverage, typically range from 30 percent to 75 percent of the insured's monthly earned income. We provide various options with respect to length of benefit periods, product features, and waiting periods before benefit payments begin, which permit tailoring of the multi-life plan to a specific employer's needs. We also market individual disability policies which include payments for the transfer of business ownership between partners and payments for business overhead expenses, also on a multi-life basis. Individual disability products do not provide for the accumulation of cash values.

Premium rates for individual disability products vary by age, product features, and occupation based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience. Our underwriting rules, issue limits, and plan designs reflect risk and the financial circumstances of prospective insureds. Individuals in multi-life groups may be subject to limited medical underwriting. The majority of our individual disability policies are written on a noncancelable basis. Under a noncancelable policy, as long as the insured continues to pay the fixed annual premium for the policy's duration, we cannot cancel the policy or change the premium.

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Profitability of individual disability insurance is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Voluntary Benefits

Voluntary benefits products are primarily sold to groups of employees through payroll deduction at the workplace and include life, disability, accident, hospital indemnity, cancer, and critical illness offered on both a group and individual basis.

Premium rates for voluntary benefits products are based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own claims and persistency experience and published industry tables. Our underwriters evaluate the medical condition of prospective policyholders prior to the issuance of a policy on a simplified basis. Underwriting requirements may be waived for cases that meet certain criteria, including participation levels. Individual voluntary benefits products other than life insurance are offered on a guaranteed renewable basis which allows us to re-price in-force policies, subject to regulatory approval. Group voluntary benefits products are offered primarily on an optionally renewable basis which allows us to re-price or terminate in-force policies.

Profitability of voluntary benefits products is affected by the level of employee participation, persistency, investment returns, claims experience, and the level of administrative expenses.

Dental and Vision

Group dental and vision products are sold to employers as employee benefit products. Our group dental products include a variety of insured and self-insured dental care plans including preferred provider organizations and scheduled reimbursement plans. Our group vision products provide coverage that includes a range of both in-network and out-of-network benefits for routine vision services offered either in conjunction with our dental product offerings or as stand-alone coverage.

Premiums for small case group dental and vision products are generally based on expected claims of a pool of similar risks plus a provision for administrative expenses, investment income, and profit. Premiums for large employer groups are underwritten on an experience-rated basis.

Profitability of our dental and vision products is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

We discontinued offering our direct-to-consumer individual dental and vision products, a portion of the Starmount Life offering, in the second half of 2018 to focus on the integration of our dental and vision products in our existing Unum US and Colonial Life distribution channels.

Unum International Segment

The Unum International segment includes our operations in the United Kingdom and Poland. Unum UK's business includes insurance for group long-term disability, group life, and supplemental lines of business which include dental, individual disability, and critical illness products. Unum Poland's business primarily includes insurance for individual and group life with accident and health riders. Both Unum UK's and Unum Poland's products are sold primarily through field sales personnel and independent brokers and consultants. Unum Poland 's results are included within the supplemental product. The market strategy for the segment is to offer benefits to employers and employees through the workplace, with a focus on the expansion of the number of employers and employees covered in our Unum UK core market segment, which we define as employee groups with fewer than 500 employees, and the growth of the existing Unum Poland business through the incorporation of our benefits and distribution expertise.

The percentage of Unum International segment premium income generated by each product line during 2018 is as follows:

Group Long-term Disability	63.1	%
Group Life	19.5
Supplemental	17.4
Total	100.0	%

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Group Long-term Disability

Group long-term disability products are sold to employers for the benefit of employees. Group long-term disability provides employees with insurance coverage for loss of income in the event of extended work absences due to sickness or injury. Services are offered to employers and insureds to encourage and facilitate rehabilitation, retraining, and re-employment. Most policies begin providing benefits following 90 or 180 day waiting periods and continue providing benefits until the employee reaches a certain age, generally between 60 and 67. The benefits are limited to specified maximums as a percentage of income.

Premiums for group long-term disability are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Some cases carry experience rating provisions. Premiums for experience-rated group long-term disability business are based on the expected experience of the client given its demographics, industry group, and location, adjusted for the credibility of the specific claim experience of the client.

We have defined underwriting practices and procedures.  If the coverage amount exceeds certain prescribed age and amount limits, we may require a prospective insured to submit evidence of insurability. Policies are typically issued, both at inception and renewal, with rate guarantees. The usual rate guarantee is two years but may vary depending on circumstances.  The profitability of the policy is dependent upon the adequacy of the rate during the rate guarantee period. The contracts provide for certain circumstances in which the rate guarantees can be overridden.

Profitability of group long-term disability insurance is affected by persistency, investment returns, claims experience, and the level of administrative expenses. Morbidity is an important factor in disability claims experience. We routinely make pricing adjustments on our group insurance products, when contractually permitted, which take into account emerging experience and external factors.

Group Life

Group life products are sold to employers as employee benefit products. Group life consists of two types of products, a renewable term life insurance product and a group dependent life product. The renewable term life product provides a lump sum benefit to the beneficiary on death of an employee. The group dependent life product, which we discontinued offering to new customers in 2012, provides an annuity to the beneficiary upon the death of an employee. Both coverages are frequently linked to employees' wages. Premiums for group life are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting and rate guarantees are similar to those utilized for group long-term disability products.

Profitability of group life is affected by persistency, investment returns, claims experience, and the level of administrative expenses.    

Supplemental

Supplemental products for our Unum UK line of business are sold to individual retail customers as well as groups of employees and include individual disability, group and individual critical illness, and group dental. Individual disability products provide the insured with a portion of earned income lost as a result of sickness or injury. Critical illness products provide a lump-sum benefit on the occurrence of a covered critical illness event. Group dental products generally provide fixed benefits based on specified treatments or a portion of the cost of the treatment. Unum Poland products, which include both individual and group life products, provide renewable term and whole life insurance with accident and health riders.

Premiums for our individual products vary by age and are based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own claims and persistency experience and published industry tables. Approximately one half of our individual disability policies are written on a noncancelable basis. The remainder of our individual disability policies and all of our individual critical illness products are offered on a guaranteed renewable basis which allows us to re-price in-force policies. Our underwriters evaluate the medical and financial condition of prospective policyholders prior to the issuance of a policy.

Premiums for group critical illness products are generally based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit. Underwriting and rate guarantees are similar to those utilized for group long-term disability products. Premiums for group dental products are generally based on standard industry rates that vary by age, with minor pricing variation based on the number of covered employees in the group.

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Premiums for Unum Poland products are based on expected claims of a pool of similar risks plus provisions for administrative expenses, investment income, and profit.

Profitability of our supplemental products is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Colonial Life Segment

Our Colonial Life segment includes insurance for accident, sickness, and disability products, which includes our expanded dental and vision products, life products, and cancer and critical illness products issued primarily by Colonial Life & Accident Insurance Company and marketed to employees, on both a group and an individual basis, at the workplace through an independent contractor agency sales force and brokers. Our market strategy for Colonial Life is to effectively deliver a broad set of voluntary products and services in the public sector market and in the commercial market, with a particular focus on the core commercial market segment, which we define for Colonial Life as accounts with fewer than 1,000 employees.

We have defined underwriting practices and procedures for each of our products. Most policies are issued on a simplified issue basis, based on answers to simple health and employment questions. If the amount applied for exceeds certain levels, the applicant may be asked to answer additional health questions or submit to additional medical examinations.

The percentage of Colonial Life segment premium income generated by each product line during 2018 is as follows:

Accident, Sickness, and Disability	57.9	%
Life	20.5
Cancer and Critical Illness	21.6
Total	100.0	%

Accident, Sickness, and Disability

The accident, sickness, and disability product line consists of short-term disability plans, accident-only plans providing benefits for injuries on a specified loss basis, and our expanded dental and vision products. It also includes accident, health, and dental plans covering hospital admissions, confinement, surgeries, and dental services on an indemnity basis.

Premiums for accident, sickness, and disability products are generally based on assumptions for morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience. Premiums are primarily individual guaranteed renewable for which we have the ability to change premiums on a state by state basis. A small percentage of the policies are written on a group basis for which we retain the right to change premiums at the individual account level. Premiums for our expanded dental and vision products are generally guaranteed issue with standard industry rates that vary by age and region.

Profitability is affected by the level of employee participation, persistency, investment returns, claims experience, and the level of administrative expenses.

The accident, health and dental products qualify as fringe benefits that can be purchased with pre-tax employee dollars under flexible benefits programs. Flexible benefits programs assist employers in managing benefit and compensation packages and provide policyholders the ability to choose benefits that best meet their needs. Laws could be changed to limit or eliminate fringe benefits available on a pre-tax basis, eliminating our ability to continue marketing our products this way. However, we believe our products provide value to our policyholders that will remain even if the tax advantages offered by flexible benefits programs are modified or eliminated.

Life

Life products are primarily comprised of universal life, whole life, and term life policies.

Premium rates vary by age and are based on assumptions concerning mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience and published industry tables. Premiums for the whole life and level term products are guaranteed for the life of the contract. Premiums for the universal life

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products are flexible and may vary at the individual policyholder level. For the group term life products, we retain the right to change premiums at the account level based on the experience of the account.

Profitability is affected by the level of employee participation, persistency, investment returns, claims experience, and the level of administrative expenses.

Cancer and Critical Illness

Cancer policies provide various benefits for the treatment of cancer including hospitalization, surgery, radiation, and chemotherapy. Critical illness policies provide a lump-sum benefit and/or fixed payments on the occurrence of a covered critical illness event.

Premiums are generally based on assumptions for morbidity, mortality, persistency, administrative expenses, investment income, and profit. We develop our assumptions based on our own experience. Premiums are primarily individual guaranteed renewable wherein we have the ability to change premiums on a state by state basis.

Profitability of these products is affected by the level of employee participation, persistency, investment returns, claims experience, and the level of administrative expenses.

Closed Block Segment

Our Closed Block segment consists of individual disability, group and individual long-term care, and other insurance products no longer actively marketed. Closed Block segment premium income for 2018 was comprised of approximately 39 percent individual disability and 61 percent group and individual long-term care.

Individual Disability

We began limiting sales of the types of individual disability policies reported in our Closed Block segment subsequent to the mid-1990s after substantial changes in product design were implemented to improve the overall risk profile of our offerings of individual disability products. We entirely discontinued issuing new policies in this closed block of business in 2004, other than through update features contractually allowable on existing policies. The majority of the policies were written on a noncancelable basis and were marketed on a single-life customer basis. Profitability is affected by persistency, investment returns, claims experience, and the level of administrative expenses.

Group and Individual Long-term Care

We discontinued offering individual long-term care in 2009 and group long-term care in 2012, other than features contractually allowable on existing group policies. Group long-term care was previously offered to employers for the benefit of employees. Individual long-term care was previously marketed on a single-life customer basis.

Long-term care insurance pays a benefit upon the loss of two or more activities of daily living and the insured's requirement of standby assistance or cognitive impairment. Payment is generally made on an indemnity basis, regardless of expenses incurred, up to a lifetime maximum. Benefits begin after a waiting period, usually 90 days or less, and are generally paid for a period of three years, six years, or lifetime.

Our long-term care insurance was sold on a guaranteed renewable basis which allows us to re-price in-force policies, subject to regulatory approval. Premium rates for long-term care vary by age and are based on assumptions concerning morbidity, mortality, persistency, administrative expenses, investment income, and profit. Premium rate increases continue to be implemented where needed and where approved by state regulators. We develop our assumptions based on our own claims and persistency experience and published industry tables.

Profitability is affected by premium rate increases, persistency, investment returns, claims experience, and the level of administrative expenses.

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Other

Other insurance products not actively marketed include group pension, individual life and corporate-owned life insurance, reinsurance pools and management operations, and other miscellaneous product lines. The majority of these products have been reinsured, with approximately 80 percent of reserves at December 31, 2018 ceded to other insurance companies.

Corporate Segment

Our Corporate segment includes investment income on corporate assets not specifically allocated to a line of business, interest expense on corporate debt other than non-recourse debt, and certain other corporate income and expense not allocated to a line of business.

Reinsurance

In the normal course of business, we assume reinsurance from and cede reinsurance to other insurance companies. In a reinsurance transaction, a reinsurer agrees to indemnify another insurer for part or all of its liability under a policy or policies it has issued for an agreed upon premium. We undertake reinsurance transactions for both risk management and capital management. If the assuming reinsurer in a reinsurance agreement is unable to meet its obligations, we remain contingently liable. In the event that reinsurers do not meet their obligations under the terms of the reinsurance agreement, reinsurance recoverable balances could become uncollectible. We evaluate the financial condition of reinsurers to whom we cede business and monitor concentration of credit risk to minimize our exposure. We may also require assets to be held in trust, letters of credit, or other acceptable collateral to support reinsurance recoverable balances. The collectibility of our reinsurance recoverable is primarily a function of the solvency of the individual reinsurers. Although we have controls to minimize our exposure, the insolvency of a reinsurer or the inability or unwillingness of a reinsurer to comply with the terms of a reinsurance contract could have a material adverse effect on our results of operations.

In general, the maximum amount of life insurance risk retained by our U.S. insurance subsidiaries under group or individual life or group or individual accidental death and dismemberment policies during 2018 was $1 million per covered life per policy. The retention amount remains at $1 million for 2019. For Unum Limited life insurance risk, during 2018 we had reinsurance agreements which provided 75 percent coverage up to £500 thousand per covered life for group dependent life benefits and 25 percent coverage for group lump sum benefits, as well as 100 percent coverage per covered life above that amount. 

We have reinsurance agreements on approximately 76 percent of our Closed Block individual disability business. As of December 31, 2018, this reinsurance covers approximately 67 percent of that portion of the consolidated risk above a $4.6 billion retention limit.  The risk limit for the reinsurer grows over time to a maximum of $2.2 billion, after which any further losses will revert to us.

We have global catastrophic reinsurance coverage which covers all Unum Group insurance companies and includes four layers of coverage to limit our exposure under life, accidental death and dismemberment, long-term care, and disability policies in regard to a catastrophic event. Each layer provides coverage for all catastrophic events, including acts of war and any type of terrorism, up to $1 million of coverage per person per policy for each U.S. and non-U.K. line of covered business, and up to £2 million of coverage for each U.K. covered line of business. We have the following coverage for 2019, after a $100 million deductible:

Layer	Coverage (in millions)		Percent Coverage
First	$	50.0	50.0	%
Second	55.0		55.0
Third	90.0		60.0
Fourth	180.0		60.0
Total Catastrophic Coverage	$	375.0

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In addition to the global catastrophic reinsurance coverage noted above, Unum Limited has additional catastrophic coverage via an arms-length, inter-company reinsurance agreement with Unum America, under similar terms as the global catastrophic treaties. Unum Limited has the following additional coverage for 2019, after a £75 million deductible:

Layer	Coverage (in millions)		Percent Coverage
First	£	15.0	20.0	%
Second	6.8		22.5
Total Catastrophic Coverage	£	21.8

Unum Poland has additional global catastrophic reinsurance coverage of up to zł70 million with a maximum retention limit of zł0.8 million in 2018. Insurable events include passive war, as well as nuclear, chemical, biological and other forms of terrorism. This agreement was renewed with the same conditions for 2019.

Events may occur which limit or eliminate the availability of catastrophic reinsurance coverage in future years.

We have a quota share reinsurance agreement under which we cede certain blocks of Unum US group long-term disability claims. The agreement is on a combination coinsurance with funds withheld and modified coinsurance basis and provides 90 percent quota share reinsurance on the ceded claims, which was increased from 80 percent during 2018 on all ceded blocks of business. We also have four reinsurance agreements that collectively cede approximately 55 percent of Unum US group life risk up to our per person retention limit for our U.S. insurance subsidiaries. These reinsurance agreements for Unum US group disability and group life allow us to more effectively manage capital in conformity with statutory accounting principles but do not meet insurance risk transfer in accordance with applicable U.S. generally accepted accounting principles (GAAP) and therefore are not accounted for as reinsurance in our consolidated GAAP financial statements.

We also cede 30 percent of the risk for certain blocks of recently issued Unum US individual disability policies, as well as some related claims development risk for a limited period of time. The agreement is on a non-proportional modified coinsurance basis with a provision for experience refunds.

Certain of our domestic insurance subsidiaries cede blocks of business to Northwind Reinsurance Company (Northwind Re) and Fairwind Insurance Company (Fairwind), both of which are affiliated captive reinsurance subsidiaries (captive reinsurers) domiciled in the United States, with Unum Group as the ultimate parent. These captive reinsurers were established for the limited purpose of reinsuring risks attributable to specified policies issued or reinsured by our insurance subsidiaries in order to effectively manage risks in connection with certain blocks of our business as well as to enhance our capital efficiency. On a consolidated reporting basis for Unum Group, financial statement impacts of our reinsurance arrangements with affiliates are eliminated in accordance with GAAP.

For further discussion of our reinsurance activities, refer to "Risk Factors" contained herein in Item 1A; "Consolidated Operating Results," "Segment Results," and "Liquidity and Capital Resources - Cash Available from Subsidiaries" contained herein in Item 7, and Notes 1, 12, and 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Reserves for Policy and Contract Benefits

The applicable insurance laws under which insurance companies operate require that they report, as liabilities, policy reserves to meet future obligations on their outstanding policies. These reserves are the amounts which, with the additional premiums to be received and interest thereon compounded annually at certain assumed rates, are calculated to be sufficient to meet the various policy and contract obligations as they mature. These laws specify that the reserves shall not be less than reserves calculated using certain specified mortality and morbidity tables, interest rates, and methods of valuation required for statutory accounting.

The reserves reported in our financial statements contained herein are calculated in conformity with GAAP and differ from those specified by the laws of the various states and reported in the statutory financial statements of our life insurance subsidiaries. These differences result from the use of mortality and morbidity tables and interest assumptions which we believe are more representative of the expected experience for these policies than those required for statutory accounting purposes and also result from differences in actuarial reserving methods.

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The assumptions we use to calculate our reserves are intended to represent an estimate of experience for the period that policy benefits are payable. If actual experience is equal, or favorable, to our reserve assumptions, then reserves should be adequate to provide for future benefits and expenses. If experience is less favorable than the reserve assumptions, additional reserves may be required. The key experience assumptions include claim incidence rates, claim resolution rates, mortality and morbidity rates, policy persistency, interest rates, premium rate increases, and any applicable policy benefit offsets, including those for social security and other government-based welfare benefits. We periodically review our experience and update our policy reserves for new issues and reserves for all claims incurred, as we believe appropriate.

The consolidated statements of income include the annual change in reserves for future policy and contract benefits. The change reflects a normal accretion for premium payments and interest buildup and decreases for policy terminations such as lapses, deaths, and benefit payments. If policy reserves using best estimate assumptions as of the date of a test for loss recognition are higher than existing policy reserves net of any deferred acquisition costs, the increase in reserves necessary to recognize the deficiency is also included in the change in reserves for future policy and contract benefits.

For further discussion of reserves, refer to "Risk Factors" contained herein in Item 1A, "Critical Accounting Estimates" and the discussion of segment operating results included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7, and Notes 1 and 6 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Investments

Investment activities are an integral part of our business, and profitability is significantly affected by investment results. We segment our invested assets into portfolios that support our various product lines. Generally, our investment strategy for our portfolios is to match the effective asset cash flows and durations with related expected liability cash flows and durations to consistently meet the liability funding requirements of our businesses. We seek to earn investment income while assuming credit risk in a prudent and selective manner, subject to constraints of quality, liquidity, diversification, and regulatory considerations. Our overall investment philosophy is to invest in a portfolio of high quality assets that provide investment returns consistent with that assumed in the pricing of our insurance products. Assets are invested predominately in fixed maturity securities. Changes in interest rates may affect the amount and timing of cash flows.

We actively manage our asset and liability cash flow match and our asset and liability duration match to limit interest rate risk. We may redistribute investments among our different lines of business, when necessary, to adjust the cash flow and/or duration of the asset portfolios to better match the cash flow and duration of the liability portfolios. Asset and liability portfolio modeling is updated on a quarterly basis and is used as part of the overall interest rate risk management strategy. Cash flows from the in-force asset and liability portfolios are projected at current interest rate levels and also at levels reflecting an increase and a decrease in interest rates to obtain a range of projected cash flows under the different interest rate scenarios. These results enable us to assess the impact of projected changes in cash flows and duration resulting from potential changes in interest rates. Testing the asset and liability portfolios under various interest rate scenarios enables us to choose what we believe to be the most appropriate investment strategy, as well as to limit the risk of disadvantageous outcomes. Although we test the asset and liability portfolios under various interest rate scenarios as part of our modeling, the majority of our liabilities related to insurance contracts are not interest rate sensitive, and we therefore have minimal exposure to policy withdrawal risk. Our determination of investment strategy relies on long-term measures such as reserve adequacy analysis and the relationship between the portfolio yields supporting our various product lines and the aggregate discount rate assumptions embedded in the reserves. We also use this analysis in determining hedging strategies and utilizing derivative financial instruments for managing interest rate risk and the risk related to matching duration for our assets and liabilities. We do not use derivative financial instruments for speculative purposes.

Refer to "Risk Factors" contained herein in Item 1A; "Critical Accounting Estimates" and the discussion of investments in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7; and Notes 1, 2, 3, and 4 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for information on our investments and derivative financial instruments.

Ratings

AM Best, Fitch Ratings (Fitch), Moody's Investors Service (Moody's), and Standard & Poor's Ratings Services (S&P) are among the third parties that assign issuer credit ratings to Unum Group and financial strength ratings to our insurance subsidiaries. Issuer credit ratings reflect an agency's opinion of the overall financial capacity of a company to meet its senior debt obligations. Financial strength ratings are specific to each individual insurance subsidiary and reflect each rating agency's

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view of the overall financial strength (capital levels, earnings, growth, investments, business mix, operating performance, and market position) of the insuring entity and its ability to meet its obligations to policyholders. Both the issuer credit ratings and financial strength ratings incorporate quantitative and qualitative analyses by rating agencies and are routinely reviewed and updated on an ongoing basis.

Rating agencies assign an outlook statement of "positive," "negative," or "developing" to indicate an intermediate-term trend in credit fundamentals which could lead to a rating change. "Positive" means that a rating may be raised, "negative" means that a rating may be lowered, and "developing" means that a rating may be raised or lowered with equal probability. Alternatively, a rating may have a "stable" outlook to indicate that the rating is not expected to change.

"Credit watch" or "under review" highlights the potential direction of a short-term or long-term rating. It focuses on identifiable events and short-term trends that cause a rating to be placed under heightened surveillance by a rating agency. Events that may trigger this action include mergers, acquisitions, recapitalizations, regulatory actions, criteria changes, or operating developments. Ratings may be placed on credit watch or under review when an event or a change in an expected trend occurs and additional information is needed to evaluate the current rating level. This status does not mean that a rating change is inevitable, and ratings may change without first being placed on a watch list. A rating is not a recommendation to buy, sell, or hold securities and may be subject to revision or withdrawal at any time by the rating agency. Each rating should be evaluated independently of any other rating.

See "Management's Discussion and Analysis of Financial Condition and Results of Operations - Ratings" contained herein in Item 7 for our current outlook, issuer credit, and financial strength ratings. See also further discussion in "Risk Factors" contained herein in Item 1A.

Competition

There is significant competition among insurance companies for the types of products we sell. We are operating in a dynamic competitive environment of both traditional and non-traditional competitors, with changes in product offerings, enrollment services, and technology solutions. We believe that the principal competitive factors affecting our business are price, quality of the customer experience regarding service and claims management, integrated product choices, enrollment capabilities, financial strength ratings, and claims-paying ratings. In the individual and group disability markets, we compete in the United States with a number of major companies and regionally with other companies offering specialty products. Our principal competitors for our other products, including group life and the product offerings sold to groups of employees through payroll deduction, include the largest insurance companies in the United States. Some of these companies have more competitive pricing or have higher claims-paying ratings. Some may also have greater financial resources with which to compete.

In both the United Kingdom and Poland, we compete for the individual and group products we sell with a mix of large internationally recognized providers and strong local carriers. 

We believe the need for the types of products we offer is significant. Individuals and families often live paycheck to paycheck with a considerable chance of being out of work.  Pressure is also mounting on governments as to the sustainability of public assistance.  Based on current penetration levels, we believe there is substantial upside growth potential.

All areas of the employee benefits markets are highly competitive due to the yearly renewable term nature of our products and the large number of insurance companies offering products in this market. There is a risk that our customers may be able to obtain more favorable terms or improved technology solutions from competitors in lieu of renewing coverage with us. The effect of competition may, as a result, adversely affect the persistency of these and other products, as well as our ability to sell products in the future.

We must attract and retain independent agents and brokers to actively market our products. Strong competition exists among insurers for agents and brokers. We compete with other insurers for sales agents and brokers primarily on the basis of our product offerings, financial strength, support services, and compensation. Sales of our products could be materially adversely affected if we are unsuccessful in attracting and retaining agents and brokers.

For further discussion, refer to "Risk Factors" contained herein in Item 1A.

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Regulation

We and our subsidiaries are subject to extensive and comprehensive supervision and regulation in the United States, the United Kingdom, and Poland. The laws and regulations with which we must comply are complex and subject to change. New or existing laws and regulations may become more restrictive or otherwise adversely affect our operations. As a result of the financial market and economic challenges in recent years, regulation and the cost of compliance with regulation has continued to increase.

Insurance Regulation and Oversight

Our U.S. insurance subsidiaries are subject to regulation and oversight by insurance regulatory authorities in the jurisdictions in which they do business and by the U.S. Department of Labor (DOL) on a national basis, primarily for the protection of policyholders. State insurance regulators in the U.S. generally have broad powers with respect to all aspects of the insurance business, including the power to: license and examine insurance companies; regulate and supervise sales practices and market conduct; license agents and brokers; approve policy forms; approve premium rates and subsequent increases thereon for certain insurance products; establish reserve requirements and solvency standards; place limitations on shareholder dividends; prescribe the form and content of required financial statements and reports; regulate the types and amounts of permitted investments; and regulate reinsurance transactions. Our U.S. insurance subsidiaries are examined periodically by their states of domicile and by other states in which they are licensed to conduct business. The domestic examinations have traditionally emphasized financial matters from the perspective of protection of policyholders, but they can and have covered other subjects that an examining state may be interested in reviewing, such as market conduct issues. Examinations in other states more typically focus on market conduct, such as a review of sales practices, including the content and use of advertising materials and the licensing and appointing of agents and brokers, as well as underwriting, claims, and customer service practices, and identification and handling of unclaimed property to determine compliance with state laws. Our U.S. insurance subsidiaries are also subject to assessments by state insurance guaranty associations to cover the proportional cost of insolvent or failed insurers. The DOL enforces a comprehensive federal statute which regulates claims paying fiduciary responsibilities and reporting and disclosure requirements for most employee benefit plans.

Our U.K. insurance subsidiary, Unum Limited, is subject to dual regulation by the Prudential Regulation Authority (PRA) and the Financial Conduct Authority (FCA). The PRA oversees the financial health and stability of financial services firms and is responsible for the prudential regulation and day-to-day supervision of insurance companies. The FCA seeks to protect consumers and oversees financial services products and practices, including those governing insurance companies in the U.K.

In June 2016, the U.K. held a referendum and voted to leave the European Union (EU). The U.K. subsequently invoked Article 50 of the Treaty and is due to leave the EU on March 29, 2019. The U.K.'s decision to leave the EU may add cost and complexity to our compliance efforts if new laws and regulations are established that significantly diverge from those currently in place, however, we are not aware of any indications of such changes in the short-term and do not expect significant changes over the longer term.

Our Polish insurance subsidiary, Unum Poland, is subject to regulation by the Komisja Nadzoru Finansowego (KNF) of the Financial Supervision Authority (FSA) in Poland. The KNF oversees the financial health and stability of financial services firms and is responsible for the prudential regulation and day-to-day supervision of insurance companies and other financial institutions.

Capital Requirements

Risk-based capital (RBC) standards for U.S. life insurance companies are prescribed by the National Association of Insurance Commissioners (NAIC). The domiciliary states of our U.S. insurance subsidiaries have all adopted a version of the NAIC RBC Model Act, which prescribes a system for assessing the adequacy of statutory capital and surplus for all life and health insurers. The basis of the system is a risk-based formula that applies prescribed factors to the various risk elements in a life and health insurer's business to report a minimum capital requirement proportional to the amount of risk assumed by the insurer. The life and health RBC formula is designed to measure annually (i) the risk of loss from asset defaults and asset value fluctuations, (ii) the risk of loss from adverse mortality and morbidity experience, (iii) the risk of loss from mismatching of asset and liability cash flow due to changing interest rates, and (iv) business risks. The formula is used as an early warning tool to identify companies that are potentially inadequately capitalized. The formula is intended to be used as a regulatory tool only and is not intended as a means to rank insurers generally. The NAIC modified the RBC factors in 2018 to reflect the lower U.S. statutory income tax rate that was enacted in 2017 which resulted in lower RBC ratios for our U.S. insurance subsidiaries, including our captive reinsurers, as of December 31, 2018. Although the RBC ratios for our insurance subsidiaries are lower than the prior

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year, the ratios continue to remain in line with our expectations and are significantly above the level that would require state regulatory action. The NAIC has also issued a proposal to implement a new and more granular RBC structure for fixed income asset capital charges. The proposed structure will expand the fixed income asset designations from six to 20 categories and will revise factor values. We do not anticipate that the new structure related to fixed income assets will be effective before year end 2019. We will continue to monitor the NAIC's activities on this issue.

The NAIC continues to review the state-based solvency regulation framework to identify opportunities to respond to national and international insurance regulatory and solvency developments. The topics of its review include capital requirements, governance and risk management, statutory accounting and financial reporting, and reinsurance. This ongoing review will likely result in significant changes to U.S. insurance regulation and solvency standards, including those for our U.S. insurance subsidiaries. One of the outcomes of the NAIC's review was the adoption of the NAIC Risk Management and Own Risk and Solvency Assessment (ORSA) Model Act which, following enactment at the state level, requires insurers to provide, at least annually, a group-level perspective on the risks of the current and future business plans and the sufficiency of capital to support those risks. All states where our traditional U.S. insurance subsidiaries are domiciled have enacted ORSA requirements, and we file an ORSA summary report annually with the applicable insurance regulators.

The NAIC has established a working group charged with developing a group capital calculation that can be used by regulators as a baseline quantitative measure in assessing the risks and financial position of insurance groups.  The initial recommendation for calculation is an RBC aggregation approach that would utilize existing regulatory calculations for legal entities within the group. Items still under development include the scope of the group of legal entities that would be subject to the calculation as well as factors to be used for non-insurance entities and non-U.S. insurance entities within the group. It is too early to predict what, if any, impact this will have on our capital requirements.

The NAIC has adopted a valuation manual containing a principles-based approach to life insurance company reserves. The effective date to begin a three-year implementation period was January 2017 and applies only to new business. The adoption of this valuation manual has not had a material impact on our statutory reserves.

In 2012, the NAIC established a subgroup to study the insurance industry's use of captive reinsurers and special purpose vehicles to transfer insurance risk and is considering ways to promote uniformity in both the approval and supervision of such reinsurers. More recently, the NAIC adopted a proposal to subject certain captive reinsurers and special purpose vehicles to the same capital requirements as traditional insurers. As the NAIC and state insurance regulators continue to examine the use of captive insurance companies to finance reserves required under current regulations, we cannot predict the ultimate outcome of their work, or how long or extensively they will continue to focus on this issue. Although we believe it to be unlikely, a potential outcome of future NAIC decisions from its various committees, task forces, and working groups is that companies could be prohibited from using captive reinsurers. No changes in the use or regulation of captive reinsurers have been proposed by the NAIC, and we are unable to predict the extent of any changes that might be made. Accordingly, we expect to continue our strategy of using captive reinsurers to manage risks and enhance capital efficiency while monitoring the NAIC's study and proposed changes in regulations. See "Reinsurance" contained herein in this Item 1 for further discussion.

The PRA has statutory requirements, including capital adequacy and liquidity requirements and minimum solvency margins, to which Unum Limited must adhere as part of the provisions of Solvency II, an EU directive that prescribes capital requirements and risk management standards for the European insurance industry.  Our European holding company is also subject to the Solvency II requirements relevant to insurance holding companies, while its subsidiaries, which includes Unum Limited, are subject to group supervision under Solvency II.  The Unum European Economic Area (EEA) Group, which is comprised of the European holding company and its subsidiaries, received approval from the PRA to use its own internal model for calculating regulatory capital and also received approval for certain associated regulatory permissions including transitional relief as the Solvency II capital regime is implemented.  Although there are currently no indications that the regulatory capital regime for our U.K. operations will change due to the U.K.'s decision to leave the EU, it remains too early to predict what, if any, impact this may have on existing capital requirements for our U.K. entities, but economic conditions may cause volatility in our solvency ratios.

The International Association of Insurance Supervisors (IAIS) is developing a Common Framework (ComFrame) for the supervision of internationally active insurance groups (IAIGs) that contemplates group-wide supervision across national boundaries, including uniform standards for insurer corporate governance and enterprise risk management, a framework for group capital adequacy assessment that accounts for group-wide risks, and the establishment of ongoing supervisory colleges. We do not qualify as an IAIG under the current criteria for designating an IAIG. However, we monitor the activities of the IAIS for the potential that ComFrame could apply to us in the future. The IAIS expects to implement an Insurance Capital Standard in the form of confidential reporting to supervisory colleges by the end of 2019. At this time, we cannot predict what,

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if any, additional capital requirements, compliance costs, or other requirements this proposed standard might impose on us, if adopted.

See further discussion in "Risk Factors" contained herein in Item 1A and "Liquidity and Capital Resources" contained herein in Item 7 and Note 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.     

Insurance Holding Company Regulation

We and our U.S. insurance subsidiaries (excluding captive reinsurers) are subject to regulation under the insurance holding company laws in the states in which our insurance subsidiaries are domiciled, which currently include Maine, Massachusetts, New York, South Carolina, and Tennessee. These laws generally require each insurance company that is domiciled in the state and a member of an insurance holding company system to register with the insurance department of that state and to furnish at least annually financial and other information about the operations of companies within the holding company system, including information concerning capital structure, ownership, management, financial condition, and certain intercompany transactions. Transactions between an insurer and affiliates in the holding company system generally must be fair and reasonable and, if material, require prior notice and approval by the domiciliary insurance regulator.

In addition, such laws and regulations restrict the amount of dividends that may be paid by our insurance subsidiaries to their respective shareholders, including our Company and certain of our intermediate holding company subsidiaries. See further discussion in "Risk Factors" contained herein in Item 1A and "Liquidity and Capital Resources - Cash Available from Subsidiaries" contained herein in Item 7.

There are a number of proposals to amend state insurance laws and regulations in ways that could affect us and our insurance subsidiaries. The NAIC has adopted or amended model laws on holding company regulation that provide for supervision of insurers at the corporate group level. The various proposals to implement group supervision include uniform standards for insurer corporate governance, group-wide supervision of insurance holding companies, adjustments to RBC calculations to account for group-wide risks, and additional regulatory and disclosure requirements for insurance holding companies, including a requirement that the ultimate controlling person of a U.S. insurer submit to the lead state insurance regulator an annual enterprise risk report, which identifies activities, circumstances, or events involving one or more affiliates of an insurer that, if not remedied properly, are likely to have a material adverse effect upon the financial condition or liquidity of the insurer or its insurance holding company system as a whole. The NAIC has adopted the Corporate Governance Annual Disclosure Model Act and the Corporate Governance Annual Disclosure Model Regulation, which require U.S. insurers to disclose detailed information regarding their governance practices. The model act and regulation must be adopted by individual state legislatures and insurance regulators in order to be effective in a particular state. At this time, among the states in which our insurance subsidiaries are domiciled, the model act and regulation are effective only in Maine, Massachusetts, and Tennessee. The NAIC adopted the Insurance Data Security Model Law, which creates a legal framework that requires insurance companies to establish cybersecurity programs designed to protect the private data of consumers. The law outlines planned cybersecurity testing, and the development of incident response plans for breach notification procedures. The model law must be adopted by individual state legislatures and insurance regulators in order to be effective in particular state. At this time, among the states in which our insurance subsidiaries are domiciled, the model law is effective only in South Carolina. The New York State Department of Financial Services has established similar regulations to this law which became effective in 2017 and the state of California has enacted the California Consumer Privacy Act of 2018.

The laws of most states, including the states in which our insurance subsidiaries are domiciled (or deemed to be commercially domiciled), require regulatory approval of a change in control of an insurance company or its holding company. Where these laws apply to us, there can be no effective change in control of our Company or of any of our insurance subsidiaries unless the person seeking to acquire control has filed a statement containing specified information with the appropriate insurance regulators and has obtained their prior approval of the proposed change. The usual measure for a presumptive change of control pursuant to these laws is the acquisition of 10 percent or more of the voting stock of an insurance company or its holding company, although this presumption is rebuttable. Consequently, a person acquiring 10 percent or more of the voting stock of an insurance company or its holding company without the prior approval of the insurance regulators in the state(s) of domicile of the insurance company(ies) sought to be acquired (or whose holding company is sought to be acquired) will be in violation of these laws. Such a person may also be subject to one or more of the following actions: (i) injunctive action requiring the disposition or seizure of those shares by the applicable insurance regulators; (ii) prohibition of voting of such shares; and (iii) other actions determined by the relevant insurance regulators. Further, many states' insurance laws require that prior notification be given to state insurance regulators of a change in control of a non-domiciled insurance company doing business in the state. These pre-notification statutes do not authorize the state insurance regulators to disapprove the change in control; however, they do authorize regulatory action in the affected state if particular conditions exist, such as undue market

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concentration. Any future transactions that would constitute a change in control of our Company or of any of our insurance subsidiaries may require prior notification in those states that have adopted pre-notification laws.

These laws may discourage potential acquisition proposals and may delay, deter, or prevent a change in control of our Company, including through transactions, and in particular unsolicited transactions, that some or all of our shareholders might consider to be desirable.

Federal Laws and Regulations

Enacted in 2010, the Dodd-Frank Wall Street Reform and Consumer Protection Act (Dodd-Frank) effected comprehensive changes to the regulation of financial services in the United States. Dodd-Frank directed various government agencies and bodies to promulgate regulations implementing the law, many of which remain to be completed. Among other provisions, Dodd-Frank created a new framework for regulation of the over-the-counter derivatives markets, including requirements that certain swaps be executed through a centralized exchange or regulated facility and be cleared through a regulated clearinghouse. It also subjected us and major swap participants to capital and margin (i.e., collateral) requirements, which generally had the effect of increasing the costs of hedging and the credit risk posed by some counterparties.

Dodd-Frank also established the Federal Insurance Office (FIO) within the Department of the Treasury, with powers over most lines of insurance, and the Financial Stability Oversight Council (FSOC). The FIO is authorized to gather data and information to monitor aspects of the insurance industry, identify issues in the regulation of insurers about insurance matters, and preempt state insurance measures under certain circumstances. Although the FIO is prohibited from directly regulating the business of insurance, the FIO may also recommend enhanced regulations to state regulatory authorities or recommend to the FSOC that it designate an insurer as a "systemically important financial institution" (SIFI). An insurer designated as a SIFI could be subject to Federal Reserve supervision and heightened regulatory standards. We have not been designated as a SIFI, and at this time we believe it is unlikely that we would be designated as such. We continue to monitor the political, legislative and regulatory environment, where possible amendments to various provisions of Dodd-Frank are under discussion.

We are subject to the laws and regulations generally applicable to public companies, including the rules and regulations of the Securities and Exchange Commission and the New York Stock Exchange relating to public reporting and disclosure, accounting and financial reporting, corporate governance, and securities trading. Further, the Sarbanes-Oxley Act of 2002, and rules and regulations adopted under this regulation, have increased the requirements for us and other public companies in these and other areas.

The USA PATRIOT Act of 2001 (Patriot Act) contains anti-money laundering and financial transparency laws and mandates the implementation of various regulations applicable to broker-dealers and other financial services companies, including insurance companies. The Patriot Act seeks to promote cooperation among financial institutions, regulators and law enforcement entities in identifying parties that may be involved in terrorism or money laundering. Anti-money laundering laws outside of the United States contain some similar provisions. Additionally, other federal laws and regulations, including the Foreign Corrupt Practices Act and regulations issued by the Office of Foreign Asset's Controls, as well as the U.K.'s Bribery Act of 2010, have increased requirements relating to identifying customers, prohibiting transactions with certain organizations or individuals, watching for and reporting suspicious transactions, responding to requests for information by regulatory authorities and law enforcement agencies, sharing information with other financial institutions, and requiring the implementation and maintenance of internal practices, procedures, and controls.

We are subject to federal income, employment, excise and other taxes related to both our U.S. and our foreign operations.  On December 22, 2017, the U.S. Federal government enacted a tax bill, H.R.1, An Act to Provide Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018, more commonly known as the Tax Cuts and Jobs Act (TCJA). The key provisions of the TCJA relevant to us are as follows:

• Establishes a corporate income tax rate of 21 percent;

• Creates a territorial tax system rather than a worldwide system, which will generally allow companies to repatriate future foreign source earnings without incurring additional U.S. taxes by providing a 100 percent exemption for the foreign source portion of dividends from certain foreign subsidiaries;

• Subjects undistributed and previously untaxed foreign earnings and profits to a one-time transition tax also referred to as a deemed repatriation toll charge;

• Creates a U.S. shareholder tax on certain foreign subsidiary income above a routine equity return on tangible depreciable business assets (Global Intangible Low-taxed Income);

• Decreases tax-deductible life and property and casualty insurance reserves;

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• Increases the amount and amortization period of acquisition costs capitalized for tax purposes;

• Reduces the maximum deduction for net operating loss (NOL) carryforwards arising in companies other than non-life insurance companies in tax years beginning after 2017 to a percentage of the taxpayer's taxable income. It also allows any NOLs generated in tax years beginning after December 31, 2017 to be carried forward indefinitely and repeals carrybacks. NOL provisions for non-life insurance companies remain unchanged from current law;

• Allows businesses to immediately write off the cost of new investments in certain qualified depreciable assets made after September 27, 2017 subject to phase downs starting in 2023;

• Eliminates or reduces certain deductions (including deductions for certain compensation arrangements, certain payments made to governments for violations of law and certain legal settlements), exclusions and credits and adds other provisions that broaden the tax base; and

• Creates a new base erosion anti-abuse tax (BEAT) that subjects certain payments made by a U.S. company to a related foreign company to additional taxes.

See "Executive Summary" and "Liquidity and Capital Resources" contained herein in Item 7 and Notes 7 and 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for discussion of the impact to our financial position and results of operations as a result of these changes.

Federal tax laws and regulations are subject to change, and any such change could materially impact our federal taxes and reduce profitability as well as capital levels in our insurance subsidiaries.  We continually monitor federal tax legislative and regulatory developments to understand their potential impact on our profitability.

For further discussion of regulation, refer to "Risk Factors" contained herein in Item 1A.

Geographic Areas

Adjusted operating revenue, which excludes net realized investment gains and losses, for our Unum International segment was approximately 6 percent of our consolidated adjusted operating revenue in 2018, 2017, and 2016. As of December 31, 2018, total assets equaled approximately 6 percent of consolidated assets and total liabilities equaled approximately 5 percent of consolidated liabilities for our Unum International segment. Fluctuations in the U.S. dollar relative to the local currencies of our Unum International segment will impact our reported operating results. See "Risk Factors" contained herein in Item 1A and "Quantitative and Qualitative Disclosures About Market Risk" contained herein in Item 7A for further discussion of fluctuations in foreign currency exchange rates. See "Reporting Segments" contained herein in this Item 1; "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7; and Note 13 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion of Unum International's operating results.

Employees

At December 31, 2018, we had approximately 9,600 full-time employees.

Available Information

Our internet website address is www.unum.com. We make available, free of charge, on or through our website our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act as soon as reasonably practicable after filing such material with the Securities and Exchange Commission.

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Executive Officers of the Registrant

Our executive officers, who are also executive officers of certain of our principal subsidiaries, were appointed by Unum Group's board of directors to serve until their successors are chosen and qualified or until their earlier resignation or removal.

Name	Age	Position
Richard P. McKenney	50	President and Chief Executive Officer and a Director
John F. McGarry	61	Executive Vice President and Chief Financial Officer
Lisa G. Iglesias	53	Executive Vice President, General Counsel
Michael Q. Simonds	45	Executive Vice President, President and Chief Executive Officer, Unum US
Timothy G. Arnold	56	Executive Vice President, President and Chief Executive Officer, Colonial Life
Peter G. O'Donnell	52	Executive Vice President, Chief Executive Officer, Unum International
Elizabeth A. Ahmed	44	Executive Vice President, People and Communications
Puneet Bhasin	56	Executive Vice President, Chief Information and Digital Officer
Breege A. Farrell	59	Executive Vice President, Chief Investment Officer

Mr. McKenney became President in April 2015 and Chief Executive Officer in May 2015. He served as Executive Vice President and Chief Financial Officer from August 2009 until April 2015, having joined the Company in July 2009. Before joining the Company, Mr. McKenney served as Executive Vice President and Chief Financial Officer of Sun Life Financial Inc., an international financial services company, from February 2007, having joined that company as Executive Vice President in September 2006.

Mr. McGarry became Executive Vice President and Chief Financial Officer in April 2015. He served as Executive Vice President, President and Chief Executive Officer, Closed Block Operations from August 2013 to April 2015, after having served as Executive Vice President, Individual Disability and Long-term Care Closed Block Operations from September 2012. He previously served as Executive Vice President, President and Chief Executive Officer, Unum UK from July 2010, and as Senior Vice President, Benefits, Individual Disability, and National Client Group Business, Unum US from January 2010. Prior to that, he served in various other capacities within Unum US, including as Senior Vice President, Benefits Operations and Risk Management from March 2008 to January 2010, and as Senior Vice President, Benefits Operations from January 2006 to March 2008. Mr. McGarry originally joined a Unum Group predecessor company in 1986.

Ms. Iglesias was named Executive Vice President, General Counsel upon joining the Company in January 2015. She served as Senior Vice President, General Counsel and Secretary of WellCare Health Plans, Inc., a managed care company, from February 2012 to December 2014, having first joined WellCare in February 2010 as Vice President, Securities and Assistant General Counsel. Prior to that, she served as General Counsel and Corporate Secretary for Nordstrom, Inc., a fashion specialty retailer, from 2007 to 2008, and as General Counsel and Secretary of Spherion Corporation, a recruiting and staffing company, from 1999 to 2007.

Mr. Simonds was named Executive Vice President, President and Chief Executive Officer, Unum US in July 2013, after having served as Senior Vice President and Chief Operating Officer, Unum US from June 2012. He previously served as Senior Vice President, Growth Operations, Unum US from July 2010, and as Senior Vice President and Chief Marketing Officer, Unum US from March 2008. Mr. Simonds originally joined a Unum Group predecessor company in 1994, left the Company in 2000 to further his education, and rejoined the Company in 2003 after serving as a consultant with McKinsey & Company, a global management consulting firm.

Mr. Arnold was named Executive Vice President, President and Chief Executive Officer, Colonial Life in January 2015, after having served as Executive Vice President, President, Colonial Life from July 2014. He previously served as Senior Vice President, Sales and Marketing, Colonial Life from August 2012, as Senior Vice President, Chief Operations Officer, Colonial Life from July 2011, and as Senior Vice President, Integrated Underwriting, Unum US from May 2010. Mr. Arnold originally joined a Unum Group predecessor company in 1985.

Mr. O'Donnell serves as Executive Vice President, Chief Executive Officer, Unum International, having been named to this position in October 2018 when the reporting segment was previously known as Unum UK. He previously served as President and Chief Executive Officer, Unum UK, from September 2012, after having joined the Company as Unum Limited's Chief Financial Officer in 2010. Prior to joining Unum Limited, Mr. O'Donnell served as Director of Group Finance at Prudential

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plc, an international financial services company, from May 2008 to May 2010. He served as Finance director at Royal & SunAlliance plc, an international financial services company, from May 2005 to May 2008.

Ms. Ahmed was named Executive Vice President, People and Communications upon joining the Company in October 2018. She served as Executive Vice President, Chief Human Resources Officer, AmTrust Financial Services, Inc., a multinational insurance holding company, from May 2015 to October 2018. Prior to that, she served as Vice President of Human Resources at Equity Trust Company, a financial services company, from May 2012 to May 2015, and as Senior Vice President of Human Resources at PNC Bank, a diversified financial services institution, from August 2008 to May 2012.

Mr. Bhasin was named Executive Vice President, Chief Information and Digital Officer after joining the Company in March 2018. He served as Executive Vice President, Corporate Operations and Recycling at Waste Management, Inc., a waste management environmental services provider, from November 2015 to March 2017. While at Waste Management, he also served as Senior Vice President, Corporate Operations from November 2014, Chief Information Officer and Senior Vice President, Technology, Logistics and Customer Service from August 2012, and Senior Vice President and Chief Information Officer from December 2009.

Ms. Farrell was named Executive Vice President, Chief Investment Officer in August 2013, after having joined the Company as Senior Vice President and Chief Investment Officer in April 2011. Before joining the Company, she held a number of executive-level investment positions within The Allstate Corporation, a personal lines insurer, including as Senior Managing Director of Allstate Investments, LLC and certain affiliated companies from January 2010 to April 2011, and as Managing Director of these companies from August 2004 to January 2010.

ITEM 1A. RISK FACTORS

We face a wide range of risks, and our continued success depends on our ability to identify and appropriately manage our risk exposures. Discussed below are factors that may adversely affect our business, results of operations, or financial condition. Any one or more of the following factors may cause our actual results for various financial reporting periods to differ materially from those expressed in any forward-looking statements made by or on behalf of the Company, including those in this document or made by us elsewhere, such as in earnings release investor calls, investor conference presentations, or press releases. See "Cautionary Statement Regarding Forward-Looking Statements" contained herein on page 1.

Sustained periods of low interest rates in the long-term investment market may adversely affect our reported net investment income and the discount rates used in reserving for our insurance products and projecting our pension obligations, which may adversely affect our results of operations or financial condition.

Declines in interest rates and/or the continuance of the current level of low interest rates and yields on fixed income investments may cause the rates of return on our investment portfolio to decrease more than expected, leading to lower net investment income than assumed in the pricing and reserving for our insurance products. An interest, or discount, rate is used in calculating reserves for our insurance products. We set our reserve discount rate assumptions based on our current and expected future investment yield for assets supporting the reserves, considering current and expected future market conditions. If the discount rate assumed in our reserve calculations is higher than our future investment returns, our invested assets will not earn enough investment income to support our future claim payments. In that case, the reserves may eventually be insufficient, resulting in the need to increase our reserves and/or increase our capital contributions to our insurance subsidiaries, either of which could have a material adverse effect on our results of operations or financial condition.

Our net periodic benefit costs and the value of our benefit obligations for our pension plans are determined based on a set of economic and demographic assumptions that represent our best estimate of future expected experience. Major assumptions used in accounting for these plans include the expected discount (interest) rate and the long-term rate of return on plan assets. We set the discount rate assumption at the measurement date for each of our plans to reflect the yield of a portfolio of high quality fixed income corporate debt instruments matched against the timing and amounts of projected future benefits. A lower discount rate increases the present value of benefit obligations and increases our costs. Our expectations for the future investment returns on plan assets are based on a combination of historical market performance, current market conditions, and future capital market assumptions obtained from external consultants and economists. The actual rate of return on plan assets is determined based on the fair value of the plan assets at the beginning and end of the measurement period. Increases or decreases in long-term interest rates as well as equity market volatility will impact the fair value of our plan assets and may result in a decrease in the funded status of our pension plans and/or increased pension costs, which may adversely affect our results of operations, financial condition, or liquidity.

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See "Reserves for Policy and Contract Benefits" contained herein in Item 1, "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7, "Interest Rate Risk" contained herein in Item 7A, and Note 9 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

Actual experience may differ from our reserve assumptions which may adversely affect our results of operations or financial condition.

Historical results may not be indicative of future performance due to, among other things, changes in our mix of business, re-pricing of certain lines of business, or any number of economic cyclical effects on our business. Reserves, whether calculated under GAAP or statutory accounting principles, do not represent an exact calculation of future benefit liabilities but are instead estimates made by us using actuarial and statistical procedures. Actual experience may differ from our reserve assumptions. There can be no assurance that our reserves will be sufficient to fund our future liabilities in all circumstances. Future loss development may require reserves to be increased, which would adversely affect earnings in current and future periods. Life expectancies may continue to increase, which could lengthen the time a claimant receives disability or long-term care benefits and could result in a change in mortality assumptions and an increase in reserves for these and other long-tailed products. Adjustments to reserve amounts may also be required in the event of changes from the assumptions regarding future morbidity (the incidence of claims and the rate of recovery, including the effects thereon of inflation and other societal and economic factors); premium rate increases; persistency; policy benefit offsets, including those for social security and other government-based welfare benefits; and interest rates used in calculating the reserve amounts, which could have a material adverse effect on our results of operations or financial condition.

See "Reserves for Policy and Contract Benefits" contained herein in Item 1, "Executive Summary" and "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7, and Notes 1 and 6 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

Unfavorable economic conditions may result in lower sales, lower premium growth and persistency, higher claims incidence, and longer claims duration, which may adversely affect our results of operations or financial condition.

We are affected by conditions in the capital markets and the general economy, primarily in the United States, the United Kingdom, Poland, and to a lesser extent, the broader global financial markets. Negative developments in the capital markets and/or the general economy could adversely affect our business and results of operations.

In particular, factors such as unemployment levels, consumer confidence levels, consumer spending, business investment, government spending, the volatility and strength of the capital markets, and inflation all affect the business and economic environment and, ultimately, the amount and profitability of our businesses. Given the nature of our products, in an economic environment characterized by higher unemployment, lower personal income, reduced consumer spending, and lower corporate earnings and investment, new product sales may be adversely affected. Our premium growth may also be negatively impacted by lower premium growth from existing customers due to lower salary growth and lower growth in the number of employees covered under an existing policy. In addition, during such periods we may experience higher claims incidence, longer claims duration, and/or an increase in policy lapses, any of which could have a material adverse effect on our results of operations or financial condition.

We and our insurance subsidiaries are subject to extensive supervision and regulation. Changes in laws and regulations that affect our industry or the customers to whom we sell our products may affect the cost or demand for our products, increase capital requirements for our insurance subsidiaries, and adversely affect our profitability, liquidity, or growth.

Our insurance subsidiaries are subject to extensive supervision and regulation in the United States and abroad. The primary purpose of insurance regulation is to protect policyholders, not stockholders. To that end, applicable laws establish regulatory authorities, including state insurance departments in the United States, the PRA in the United Kingdom, and the KNF in Poland, with broad administrative powers over many aspects of the insurance business. For example, our insurance subsidiaries may not be able to obtain or maintain necessary licenses, permits, authorizations, or accreditations, or may be able to do so only at great cost. In addition, we and our insurance subsidiaries may not be able to comply fully with, or obtain appropriate exemptions from, the wide variety of laws and regulations applicable to insurance companies and insurance holding companies. These laws and regulations can be complex and subject to differing interpretations and are regularly re-examined. Existing or future laws and regulations, and the manner in which they are interpreted or applied, may become more restrictive or otherwise adversely affect our operations. For example, they may restrict or prohibit the payment of dividends by our subsidiaries to us,

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restrict transactions between subsidiaries and/or between us and our subsidiaries, and may require contributions of capital by us to our insurance subsidiaries even if we are otherwise in compliance with stated requirements. Failure to comply with or to obtain appropriate exemptions under any applicable laws or regulations could result in restrictions on the ability of our insurance subsidiaries to do business in one or more of the jurisdictions in which they operate and could result in fines and other sanctions, which may have a material adverse effect on our business or results of operations.

It is possible that there will be heightened oversight of insurers by regulatory authorities in the jurisdictions in which our insurance subsidiaries are domiciled and operate. We cannot predict specific proposals that might be adopted, or what impact, if any, such proposals or, if enacted, such laws, could have on our business, results of operations, or financial condition. For instance, the NAIC or state regulators may adopt revisions to the RBC formula, the PRA may revise its capital adequacy requirements and minimum solvency margins, the IAIS may adopt capital requirements to which we could be subject, or rating agencies may incorporate higher capital thresholds into their quantitative analyses, thus requiring additional capital contributions by us to our insurance subsidiaries. Increased financial services regulation, which could include activities undertaken by the NAIC and regulatory authorities in the U.K., Poland, and the EU may impose greater quantitative requirements, supervisory review, and disclosure requirements and may impact the business strategies, capital requirements, and profitability of our insurance subsidiaries. The United Kingdom's Financial Ombudsman Service, which was established to help settle disputes between consumers and businesses providing financial services, and the FCA, which has rule-making, investigative, and enforcement powers to protect consumers, may hamper our ability to do business, which could have a material adverse effect on our U.K. operations.

We use affiliated captive reinsurers for the limited purpose of reinsuring risks attributable to specified policies issued or reinsured by our insurance subsidiaries in order to effectively manage risks in connection with certain blocks of our business as well as to enhance our capital efficiency. If we were required to discontinue use of the captive reinsurers or to alter the structure of the captive reinsurance arrangements, our ability to maintain current RBC ratios and/or our capital deployment activities could be adversely affected.

Changes in U.S. programs such as healthcare reform and financial services sector reform may compete with or diminish the need or demand for our products, particularly as it may affect our ability to sell our products through employers or in the workplace. The U.S. social security disability insurance program may not be sustainable, which may adversely affect the level of our disability claim payments and reserves. Legislative changes related to pension funding requirements could negatively impact our cash flows from operations and our profitability.

Changes in tax laws and other regulations or interpretations of such laws or regulations could unfavorably impact our corporate taxes. In addition, changes in tax laws could make some of our products less attractive to consumers.

Negotiations regarding the U.K.'s plans to leave the EU on March 29, 2019 are ongoing and the anticipated resolutions remain uncertain. The magnitude and longevity of potential negative economic impacts on the growth of our Unum UK business will depend on whether an agreement is reached between the U.K. and EU as a result of exit negotiations and, if reached, the nature of the agreement and the resulting response of the U.K. marketplace. We do not expect that the underlying operations of our U.K. business to be significantly impacted by the U.K.'s exit from the EU. The insurance policies issued by our U.K. insurance subsidiary are almost exclusively written in the U.K. and cover policyholders based in the U.K. These policies will not be affected by the U.K.'s exit nor will we need to obtain additional insurance licenses to be able to continue writing these policies. For the small amount of contracts and coverages provided to companies and individuals outside of the U.K., we have developed contingency plans that could be invoked following the U.K.'s exit. The employees that support our U.K. business reside in the U.K. and will not need to change residence status after the exit. We may experience volatility in the fair values of our investments in U.K. and EU-based issuers, but we do not expect a material increase in other-than-temporary impairments or defaults, nor do we believe this volatility will impact our ability to hold these investments. We may also experience higher claims incidence in the near term, which is generally correlated to periods of economic uncertainty. Additionally, it is possible that there are tax impacts associated with the exit such as revised or new tax regulations. The continued dampening of growth due to the current disruption and uncertainty in the U.K. economy may lead to lower near-term sales and premium growth. There are currently no indications that capital requirements for our U.K. operations will change, but economic conditions may cause volatility in our solvency ratios. Our reported consolidated financial results may be unfavorably impacted by the weakening of the British pound sterling relative to preceding periods.

Dodd-Frank directs various government agencies and bodies to promulgate regulations implementing the law, an ongoing process that continues to develop. As a result of the regulations implemented thus far, regulations directed at some derivative activities and the implementation of central clearing rules have increased the cost of some hedging activities primarily as a result of more restrictive collateral requirements. We cannot predict the requirements of the remaining regulations that might

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ultimately be adopted, whether existing requirements will be repealed or changed, or how or whether such regulations will affect our businesses, results of operations, cash flows, or financial condition, require us to raise additional capital, or result in a downgrade of our credit ratings.

Most group long-term and short-term disability plans we administer are governed by the Employee Retirement Income Security Act (ERISA). Changes to ERISA enacted by Congress or through judicial interpretations may adversely affect the risk to us of managing employee benefit plans, increase the premiums associated with such plans, and ultimately affect their affordability and our profitability.

The insurance departments in jurisdictions wherein our insurance subsidiaries conduct business may limit our ability to obtain rate increases under guaranteed renewable contracts or could require changes in rates and/or benefits to meet minimum loss ratio requirements which could negatively impact the profitability of our products. Many regulatory and governmental bodies have the authority to review our products and business practices and those of our agents and employees. These regulatory or governmental bodies may bring regulatory or other legal actions against us if, in their view, our practices are improper. These actions could result in substantial fines or restrictions on our business activities and could have a material adverse effect on our business or results of operations.

Regulatory examinations or investigations could result in, among other things, changes in our claims handling or other business practices, changes in procedures for the identification and payment to the states of benefits and other property that is not claimed by the owners, changes in the use and oversight of reinsurance, increases to reserving requirements, changes in governance and other oversight procedures, assessments by tax authorities or other governing agencies, fines, and other administrative action, which could injure our reputation, adversely affect our issuer credit ratings and financial strength ratings, place us at a competitive disadvantage in marketing or administering our products, impair our ability to sell or retain insurance policies, and/or have a material adverse effect on our results of operations or financial condition. Determination by regulatory authorities that we have engaged in improper conduct may also adversely affect our defense of various lawsuits.

See "Regulation" contained herein in Item 1 and Notes 7 and 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

A cyber attack or other security breach could disrupt our operations, result in the unauthorized disclosure or loss of confidential data, damage our reputation or relationships, and expose us to significant financial and legal liability, which may adversely affect our business, results of operations, or financial condition.

We store confidential information about our business and our policyholders, employees, agents and others on our information technology systems, including proprietary and personally identifiable information. As part of our normal business operations, we use this information and engage third-party providers, including outsourcing, cloud computing, and other business partners, that store, access, process, and transmit such information on our behalf. We devote significant resources and employ security measures to help protect our information technology systems and confidential information, and we have programs in place to detect, contain, and respond to information security incidents. However, because the techniques used to obtain unauthorized access, disable or degrade service, or sabotage systems change frequently and may be difficult to detect for long periods of time, we and our third-party providers may be unable to anticipate these techniques or implement adequate preventative measures. In addition, hardware, software, or applications we develop or procure from third parties or through open source solutions may contain defects in design or manufacture or other problems that could unexpectedly compromise our information security. Unauthorized parties, whether within or outside our company, may disrupt or gain access to our systems, or those of third parties with whom we do business, through human error, misfeasance, fraud, trickery, or other forms of deceit, including break-ins, use of stolen credentials, social engineering, phishing, or other cyber attacks, computer viruses, malicious codes, and similar means of unauthorized and destructive tampering.

We and our third-party providers have experienced and likely will continue to experience information security incidents from time to time. Although known incidents have not had a material effect on our business or financial condition, there is no assurance that our security systems and measures will be able to prevent, mitigate, or remediate future incidents that could have such an effect. A successful penetration or circumvention of the security of our information technology systems, or those of third parties with whom we do business, could cause serious negative consequences for us, including significant disruption of our operations, unauthorized disclosure or loss of confidential information, harm to our brand or reputation, loss of customers and revenues, violations of privacy and other laws, and exposure to litigation, monetary damages, regulatory enforcement proceedings, fines, and potentially criminal proceedings and penalties. If we are unaware of the incident for some time after it occurs, our exposure could increase. In addition, the costs to address or remediate systems disruptions or security threats or vulnerabilities, whether before or after an incident, could be significant. As we continue to build our digital capabilities and

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focus on enhancing the customer experience, the amount of information that we retain and share with third parties is likely to grow, increasing the cost to prevent data security breaches and the cost and potential consequences of such breaches. An information technology systems failure could also interfere with our ability to comply with financial reporting and other regulatory requirements, exposing us to potential disciplinary action by regulators. Further, successful cyber-attacks at other large financial institutions or other market participants, whether or not we are affected, could lead to a general loss of customer and investor confidence in financial institutions that could negatively affect us.

Although we have insurance against some cyber risks and attacks, we may be subject to litigation and financial losses that exceed our policy limits, are subject to deductibles or are not covered under any of our current insurance policies.

The failure of our business recovery and incident management processes to resume our business operations in the event of a natural catastrophe, cyber attack, or other event could adversely affect our profitability, results of operations, or financial condition.

In the event of a disaster such as a natural catastrophe, an epidemic, a cyber attack, cyber security breach or other information technology systems failure, a terrorist attack, or war, unanticipated problems with our disaster recovery systems could have a material adverse impact on our ability to conduct business and on our results of operations and financial condition, particularly if those problems affect our information technology systems and destroy valuable data or result in a significant failure of our internal control environment. In addition, in the event that a significant number of our employees were unavailable in the event of a disaster, our ability to effectively conduct business could be severely compromised.

The failure of our information technology and/or disaster recovery systems for any reason could cause significant interruptions or malfunctions in our or our customers’ operations and result in the loss, theft, or failure to maintain the security, confidentiality or privacy of sensitive data, including personal information relating to our customers. Such a failure could harm our reputation, subject us to regulatory sanctions, legal claims, and increased expenses, and lead to a loss of customers and revenues.

In addition to interest rate risk as previously discussed, we are exposed to other risks related to our investment portfolio which may adversely affect our results of operations, financial condition, or liquidity.

Default Risk

Our investment portfolio consists primarily of fixed maturity securities. These securities are issued by both domestic and foreign entities and are backed either by collateral or the credit of the underlying issuer. Factors such as an economic downturn or political change in the country of the issuer, a regulatory change pertaining to the issuer's industry, a significant deterioration in the cash flows of the issuer, unforeseen accounting irregularities or fraud committed by the issuer, widening risk spreads, ratings downgrades, a change in the issuer's marketplace or business prospects, or other events that adversely affect the issuers of these securities may result in the issuer defaulting on its obligations.

Our mortgage loan portfolio has default risk. Events or developments, such as economic conditions that impact the ability of tenants to pay their rents or limit the availability of refinancing, may have a negative effect on our mortgage loan portfolio. Events or developments that have a negative effect on any particular geographic region or sector may have a greater adverse effect on an investment portfolio to the extent that the portfolio is concentrated in that region or sector.

A default results in the recognition of an impairment loss on the investment. A default may also adversely affect our ability to collect principal and interest due to us. The probability of credit downgrades and defaults increases when the fixed income markets experience periods of volatility and illiquidity.

Credit Spread Risk

Our exposure to credit spreads, which is the yield above comparable U.S. Treasury securities, primarily relates to market price and cash flow variability associated with changes in credit spreads. A widening of credit spreads may unfavorably impact the net unrealized gain or loss position of the investment portfolio and may adversely impact liquidity. Credit spread tightening may reduce net investment income associated with new purchases of fixed income securities.

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Valuation Risk

We report our fixed maturity securities and certain other financial instruments at fair value. Valuations may include inputs and assumptions that are less observable or require greater estimation, particularly during periods of market disruption, resulting in values which may be less than the value at which the investments may ultimately be sold. Further, rapidly changing and unprecedented credit and equity market conditions could materially impact the valuation of securities as reported in our financial statements, and the period to period changes in value could vary significantly. Decreases in value may have a material adverse effect on our results of operations or financial condition.

We evaluate our investment portfolio for impairments. There can be no assurance that we have accurately assessed the level of impairments taken. Additional impairments may need to be taken in the future, and historical trends may not be indicative of future impairments. Any event reducing the value of our securities other than on a temporary basis may have a material adverse effect on our business, results of operations, or financial condition.

Market Timing and Liquidity Risk

While we attempt to match our asset cash flows and durations with expected liability cash flows and durations to meet the funding requirements of our business, there may at times be a lack of appropriate investments in the market which can be acquired. In addition, we may, in certain circumstances, need to sell investments due to changes in regulatory or capital requirements, changes in tax laws, rating agency decisions, and/or unexpected changes in liquidity needs. There may also be a limited market for certain of our investments, such as our private placement fixed maturity securities, mortgage loans, and policy loans, which makes them more illiquid. In periods of market volatility or disruption, other of our securities may also experience reduced liquidity. If events occur wherein we need to sell securities in an unfavorable interest rate or credit environment or need to quickly sell securities which are illiquid, market prices may be lower than what we might realize under normal circumstances, with a resulting adverse effect on our results of operations, financial condition, or liquidity.

See "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 and Notes 1, 2, 3, and 4 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion of our investments and derivatives. 

Competition may adversely affect our market share or profitability.

All of our businesses are highly competitive. We believe that the principal competitive factors affecting our business are price, the quality of our customer's experience regarding service and claims management, integrated product choices, enrollment capabilities, financial strength, and claims-paying ratings. We compete for new product sales, the retention of existing business, and the ability to attract and retain independent agents and brokers to market our products, all of which affect our profitability. All areas of the employee benefits markets are highly competitive due to the yearly renewable term nature of the group products and the large number of insurance companies offering products in this market. There is a risk that our customers may be able to obtain more favorable terms or improved technology solutions from competitors in lieu of renewing coverage with us, particularly if industry pricing levels do not align with our view of adequate premium rates. We are operating in a dynamic competitive environment of both traditional and non-traditional competitors, with changes in product offerings, enrollment capabilities, and technology solutions. The level and intensity of competition may also grow due to existing competitors becoming more aggressive, and an increase in merger and acquisition activity which may result in larger competitors with greater financial resources. There are many insurance companies which actively compete with us in our lines of business, and there is no assurance that we will be able to compete effectively against these companies and new competitors in the future. See "Competition" contained herein in Item 1 for further discussion.

A decrease in our financial strength or issuer credit ratings may adversely affect our competitive position, our ability to hedge our risks, and our cost of capital or ability to raise capital, which may adversely affect our results of operations, financial condition, or liquidity.

We compete based in part on the financial strength ratings provided by rating agencies. A downgrade of our financial strength ratings may adversely affect us and could potentially, among other things, adversely affect our relationships with distributors of our products and services and retention of our sales force, negatively impact persistency and new sales, and generally adversely affect our ability to compete. A downgrade in the issuer credit rating assigned to Unum Group can be expected to adversely affect our cost of capital and our ability to raise additional capital. If we are downgraded significantly, ratings triggers in our derivatives financial instrument contracts may result in our counterparties enforcing their option to terminate the derivative contracts. Such an event may have a material adverse effect on our financial condition or our ability to hedge our risks.

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See "Ratings" contained herein in Item 1 and in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 for further discussion.

The failure to effectively execute upgrades to or replacements of information technology systems could adversely affect our business, results of operations, or financial condition.

We rely heavily on the effective operation of our information technology systems to administer our business and support the investments we are making to offer digital capabilities to enhance our customers' experience. Although we believe we have information technology systems which adequately support our business needs, we continually upgrade our existing information technology systems and acquire or develop new systems to keep pace with the rapidly changing business and technology environment. There are risks involved with upgrading or replacing information technology systems, including, but not limited to, data loss, data errors, and disruption to our operations. We seek to monitor and control our exposure to the risks arising out of these activities through our risk control framework which encompasses a variety of reporting systems, internal controls, management review processes, and other mechanisms.

Events that damage our reputation may adversely affect our business, results of operations, or financial condition.

There are many events which may harm our reputation, including, but not limited to, those discussed in this Item 1A regarding regulatory investigations, legal proceedings, and cyber or other information security incidents.

In addition, as an insurance company, we are paid to accept certain risks. Those who conduct our business, including executive officers and members of management, sales managers, investment professionals, and to some extent, independent agents and brokers, do so in part by making decisions that involve exposing us to risk. These include decisions such as maintaining effective underwriting and pricing discipline, maintaining effective claim management and customer service performance, managing our investment portfolio and derivatives trading activities, delivering effective technology solutions, complying with established sales practices, executing our capital management strategy, exiting a line of business and/or pursuing strategic growth initiatives, and other decisions. Although we employ controls and procedures designed to monitor business decisions and prevent us from taking excessive risks or unintentionally failing to comply with internal policies and practices such that errors occur, there can be no assurance that these controls and procedures will be effective. If our employees and business associates take excessive risks and/or fail to comply with internal policies and practices, the impact of those events may damage our market position and reputation.

Depending on the severity of the damage to our reputation, we may be unable to effectively compete for new products or retain our existing business, which could adversely affect our results of operations or financial condition. Damage to our reputation may also hinder our ability to raise new capital and/or increase our cost of capital. See "Regulation" contained herein in Item 1 and Note 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for additional information on regulatory matters and legal proceedings.

We provide a broad array of disability, long-term care, group life, and voluntary insurance products that are affected by many factors, and changes in any of those factors may adversely affect our results of operations, financial condition, or liquidity.

Disability Insurance

Disability insurance may be affected by a number of social, economic, governmental, competitive, and other factors. Changes in societal attitudes, such as work ethic, motivation, or stability, can significantly affect the demand for and underwriting results from disability products.

Both economic and societal factors can affect claim incidence and recoveries for disability insurance. Claim incidence and claim recovery rates may be influenced by, among other factors, the rate of unemployment and consumer confidence. Claim incidence and claim recovery rates may also be influenced by the emergence of new infectious diseases or illnesses. Claim durations may be extended by medical improvements which could extend life expectancies. The relationship between these and other factors and overall incidence is very complex and will vary due to contract design features and the degree of expertise within the insuring organization to price, underwrite, and adjudicate the claims.

Within the group disability market, pricing and renewal actions can be taken to react to higher claim rates. However, these actions take time to implement, and there is a risk that the market will not sustain increased prices. In addition, changes in economic and external conditions may not manifest themselves in claims experience for an extended period of time. The pricing actions available in the individual disability market differ among product classes. Our individual noncancelable

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disability policies, in which the policy is guaranteed to be renewable through the life of the policy at a fixed premium, do not permit us to adjust premiums on our in-force business. Guaranteed renewable contracts that are not noncancelable can be re-priced to reflect adverse experience, but rate changes cannot be implemented as quickly as in the group disability market.

Long-term Care Insurance

Long-term care insurance can be affected by a number of demographic, medical, economic, governmental, competitive, and other factors. Because long-term care insurance is a relatively new product for the insurance industry and is long-duration in nature, there is not as much historical data as is available for our other products. This creates a level of uncertainty in properly pricing the product and using appropriate assumptions when establishing reserves. Long-term care insurance is guaranteed renewable and can be re-priced to reflect adverse experience, but the re-pricing is subject to regulatory approval by our states of domicile and may also be subject to approval by jurisdictions in which our policyholders reside. The rate approval process can affect the length of time in which the re-pricing can be implemented, if at all, and the rate increases ultimately approved may be favorable or unfavorable relative to assumptions used to establish our reserves. We monitor our own experience and industry studies concerning morbidity, mortality, and policyholder terminations to understand emerging trends.  Changes in actual experience relative to our expectations may adversely affect our profitability and reserves.  Mortality continues to improve for the general population, and life expectancy has increased, which could lengthen the time a claimant receives long-term care benefits and may subject more policyholders to advanced aging and an associated increase in claims incidence. Medical advances may continue to have an impact on claim incidence and duration, both favorable and unfavorable. Due to the long duration of the product, the timing and/or amount of our investment cash flows are difficult to match to those of our maturing liabilities. Sustained periods of low or declining interest rates could result in increases in reserves and adversely affect our results of operations.

Group Life Insurance

Group life insurance may be affected bythe characteristics of the employees insured, the amount of insurance employees may elect voluntarily, our risk selection process, our ability to retain employer groups with favorable risk characteristics, the geographical concentration of employees, and mortality rates. Claim incidence may also be influenced by unexpected catastrophic events such as terrorist attacks, natural disasters, and pandemic health events, which may also affect the cost of and availability of reinsurance coverage.

Voluntary Products

Voluntary products sold in the workplace may be affected by the characteristics of the employees insured, the level of employee participation and the amount of insurance the employees elect, our risk selection process, and our ability to retain employer groups with favorable risk characteristics.  Our voluntary life insurance products generally include interest sensitive forms of insurance which contain a guaranteed minimum interest crediting rate. It is possible that our investment returns could be lower than the guaranteed crediting rate.  The non-life contracts are guaranteed renewable and can be repriced to reflect adverse experience, but rate changes cannot be implemented as quickly as for group disability and group life products.

See "Reserves for Policy and Contract Benefits" contained herein in Item 1 and "Executive Summary" and "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 for further discussion.

Changes in accounting standards may materially affect our financial statements.

Our financial statements are subject to the application of generally accepted accounting principles, in the United States, the United Kingdom, and Poland, which are periodically revised and/or expanded. Accordingly, we are required to adopt new or revised accounting standards issued by recognized authoritative bodies, including the U.S. Financial Accounting Standards Board (FASB), the U.K. Accounting Standards Board (ASB), and the NAIC. Accounting standards issued by the FASB and ASB may be influenced by the International Accounting Standards Board (IASB). Future accounting standards we adopt, including the FASB's accounting standard update related to long-duration target improvements for insurance contracts, will change current accounting and disclosure requirements applicable to our financial statements. Such changes may have a material effect on our reported results of operations or financial condition.

See Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for additional information regarding accounting updates.

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Our risk management program may leave us exposed to unidentified or unanticipated risk, which could negatively affect our business.

We have devoted significant resources to develop our enterprise risk management program, which has the objective of managing our strategic, market, credit, insurance, and operations risks, which ultimately impact our reputational risk. However, our program may not be comprehensive, and our methods for monitoring and managing risk may not fully predict or mitigate future exposures. See "Quantitative and Qualitative Disclosures About Market Risk" contained herein in Item 7A for further information about our risk management program.

Litigation and contingencies are common in our businesses and may result in financial losses and/or harm to our reputation.

We are, and in the future may be, defendants in a number of litigation matters, and the outcome of this litigation is uncertain.  Some of these proceedings have been brought on behalf of various alleged classes of complainants. Plaintiffs in class action and other lawsuits against us may seek very large and/or indeterminate amounts, including punitive and treble damages. An estimated loss is accrued when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. An adverse outcome in one or more of these actions may, depending on the nature, scope and amount of the ruling, materially and adversely affect our results of operations or financial condition, encourage other litigation, and limit our ability to write new business, particularly if the adverse outcomes negatively impact certain of our ratings.

As part of our normal operations in managing claims, we are engaged in claim litigation where disputes arise as a result of a denial or termination of benefits. Typically those lawsuits are filed on behalf of a single claimant or policyholder, and in some of these individual actions punitive damages are sought, such as claims alleging bad faith in the handling of insurance claims. For our general claim litigation, we maintain reserves based on experience to satisfy judgments and settlements in the normal course. We expect that the ultimate liability, if any, with respect to general claim litigation, after consideration of the reserves maintained, will not be material to our financial condition. Nevertheless, given the inherent unpredictability of litigation, it is possible that an adverse outcome in certain claim litigation involving punitive damages may, from time to time, have a material adverse effect on our results of operations. We are unable to estimate a range of reasonably possible punitive losses.

See "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 and Note 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for additional information on legal proceedings.

Reinsurance may not be available or affordable, or reinsurers may be unwilling or unable to meet their obligations under our reinsurance contracts, which may adversely affect our results of operations or financial condition.

As part of our overall risk management and capital management strategies, we purchase reinsurance for certain risks underwritten by our various businesses. Market conditions beyond our control determine the availability and cost of reinsurance. Any decrease in the amount of reinsurance will increase our risk of loss and may impact the level of capital requirements for our insurance subsidiaries, and any increase in the cost of reinsurance will, absent a decrease in the amount of reinsurance, reduce our results of operations. Accordingly, we may be forced to incur additional expenses for reinsurance or may be unable to obtain sufficient reinsurance on acceptable terms, which may adversely affect our ability to write future business, result in the assumption of more risk with respect to the policies we issue, and increase our capital requirements. The collectibility of our reinsurance recoverable is primarily a function of the solvency of the individual reinsurers. We cannot provide assurance that our reinsurers will pay the reinsurance recoverables owed to us or that they will pay these recoverables on a timely basis. The insolvency of a reinsurer or the inability or unwillingness of a reinsurer to comply with the terms of a reinsurance contract may have an adverse effect on our results of operations or financial condition.

The effectiveness of our hedging programs may be affected by changes in the economic environment, changes in interest rates, capital market volatility, non-performance by our counterparties, changes in the level of required collateral, or regulation, which may adversely affect our results of operations, financial condition, or liquidity.

We use derivative financial instruments to help us manage certain risks related to our business operations, primarily interest rate risk, risk related to matching duration for our assets and liabilities, and foreign currency risk. Factors associated with derivative financial instruments could adversely affect our results of operations, financial condition, or liquidity. Ineffectiveness of our hedges due to changes in expected future events, such as the risk created by uncertainty in the economic environment or if our counterparties fail or refuse to honor their obligations under these derivative instruments, may have a material adverse effect on our results of operations or financial condition. Capital market turmoil may result in an increase in the risk of non-performance

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by our counterparties, many of which are financial institutions. Non-performance by our counterparties may force us to unwind hedges, and we may be unable to replace the hedge, thereby leaving the risk unhedged. Under the terms of our hedging contracts, we are required to post collateral and to maintain a certain level of collateral, which may adversely affect our liquidity and could subject us to the credit risk of the counterparty to the extent it holds such collateral. Changes in regulations may have an adverse effect on our ability to execute hedging strategies due to the increased economic cost of derivatives, primarily as a result of more restrictive collateral requirements. We are monitoring the developments surrounding the transition from the London Interbank Offered Rate (LIBOR) expected to occur in 2021 and the impact, if any, to our existing and future derivative financial instruments and our hedging programs.

Currency translation could materially impact our reported operating results.

The functional currency of our U.K. and Polish operations is the British pound sterling and the Polish zloty, respectively. Fluctuations in exchange rates have an effect on our reported financial results, which may be unfavorably impacted when the functional currency weakens. However, it is important to distinguish between translating and converting foreign currency. Except for a limited number of transactions, we do not actually convert our functional currency into dollars. As a result, we view foreign currency translation as a financial reporting item and not a reflection of operations or profitability in the U.K or Poland.

Unum Group depends on the ability of its subsidiaries to transfer funds to it so that it can meet its obligations and pay dividends. Our ability to transfer funds to Unum Group may be impaired by adverse financial results or a change in capital requirements. Accordingly, internal sources of capital and liquidity may not always be sufficient. If we need to seek external capital, adverse market conditions may affect our access to capital or our cost of capital.

Unum Group is a holding company for insurance and other subsidiaries and has no significant operations of its own. Our insurance subsidiaries are subject to insurance laws and regulatory limitations on the payment of dividends and on other transfers of funds or other assets to affiliates, including to Unum Group. The level of earnings and capital in our subsidiaries, as well as business conditions and rating agency considerations, could impact our insurance and other subsidiaries' ability to pay dividends or to make other transfers of funds to Unum Group, which could impair our ability to pay dividends to Unum Group's common stockholders, meet our debt and other payment obligations, and/or repurchase shares of Unum Group's common stock. The use of funds held by Unum Group as consideration in any acquisition could affect our capital plan and render those funds unavailable for other corporate purposes.

A change in demand for our insurance products or an increase in the incidence of new claims or the duration of existing claims could negatively impact our cash flows from operations. Deterioration in the credit market, which could delay our ability to sell our positions in certain of our fixed maturity securities in a timely manner, could also negatively impact our cash flows. Regulatory changes such as those discussed herein in this Item 1A may impose higher capital or reserve requirements on our insurance subsidiaries, increase collateral requirements for certain of our derivatives transactions, and/or implement other requirements which could unfavorably affect our liquidity. Without sufficient liquidity, our ability to maintain and grow our operations would be limited. If our internal sources of liquidity prove to be insufficient, we may be unable to successfully obtain additional financing and capital on favorable terms, or at all, which may adversely affect us.

If our financial results are unfavorable, we may need to increase our capital in order to maintain our credit ratings or satisfy regulatory requirements. Maintaining appropriate levels of statutory surplus is considered important not only by us but by insurance regulatory authorities in the U.S., the PRA in the U.K., the KNF in Poland, and the rating agencies that rate insurers' claims-paying abilities and financial strength. Failure to maintain certain levels of statutory surplus could result in increased regulatory scrutiny, action by regulatory authorities, or a downgrade by the rating agencies. Need for additional capital may limit a subsidiary's ability to distribute funds to our holding companies.

Obtaining financing for even a small amount of capital could be challenging in unfavorable market conditions and during periods of economic uncertainty. The markets may exert downward pressure on availability of liquidity and credit capacity for certain issuers. The availability of financing will depend on a variety of factors such as market conditions, the general availability of credit, the overall availability of credit to the financial services industry, our credit ratings and credit capacity, and the possibility that customers or lenders could develop a negative perception of our financial prospects. Similarly, our access to funds may be impaired if regulatory authorities or rating agencies take negative actions against us. Raising capital in unfavorable market conditions could increase our interest expense or negatively impact our shareholders through increased dilution of their common stock in Unum Group.

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We rely on our credit facility as a potential source of liquidity. Our right to borrow funds under this facility is subject to financial covenants, negative covenants, and events of default. Our ability to borrow under this facility is also subject to the continued willingness and ability of the lenders to provide funds. Our failure to comply with the covenants in the credit facility or the failure of lenders to fund their lending commitments would restrict our ability to access this facility when needed, with a resulting adverse effect on our results of operations, financial condition, or liquidity.

We are also monitoring the developments surrounding the transition from LIBOR to determine the impact, if any, to our existing and future debt arrangements.

See "Regulation" contained herein in Item 1,"Liquidity and Capital Resources" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7, and Notes 8 and 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

We have assets which may not be fully recoverable or realizable, which could adversely affect our results of operations or financial condition.

If our business does not perform well or as initially anticipated in our assumptions, we may be required to accelerate amortization or recognize an impairment loss on intangible assets or long-lived assets or to establish a valuation allowance against the deferred income tax asset.

We have intangible assets such as deferred acquisition costs (DAC), value of business acquired (VOBA), and goodwill. DAC and VOBA are amortized based primarily upon expected future premium income of the related insurance policies. Recoverability testing for DAC and VOBA is performed on an annual basis. Insurance contracts are grouped on a basis consistent with our manner of acquiring, servicing, and measuring profitability of the contracts. If recoverability testing indicates that either DAC and/or VOBA are not recoverable, the deficiency is charged to expense.

Goodwill is not amortized, but on an annual basis, or more frequently if necessary, we review the carrying amount of goodwill for indications of impairment, considering in that review the financial performance and other relevant factors. In accordance with accounting guidance, we test for impairment at either the operating segment level or one level below. In addition, certain events including, but not limited to, a significant adverse change in legal factors or the business environment, an adverse action by a regulator or rating agency, or unanticipated competition would cause us to review goodwill for impairment more frequently than annually.

Long-lived assets, including assets such as real estate and information technology software, also require impairment testing to determine whether changes in circumstances indicate that we may be unable to recover the carrying amount.

We assess our deferred tax assets to determine if they are realizable. Factors in our determination include the performance of the business, including the ability to generate future taxable income. If based on available information, it is more likely than not that the deferred income tax asset will not be realized, a valuation allowance is established with a corresponding charge to net income.

Charges such as accelerated amortization, impairment losses, or the establishment of valuation allowances could have a material adverse effect on our results of operations or financial condition.

See "Executive Summary" and "Critical Accounting Estimates" included in "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained herein in Item 7 and Notes 1, 7, and 13 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

The continued threat of terrorism and ongoing military actions may adversely affect the value of certain assets in our investment portfolio, disrupt our operations, or result in higher claim costs.

The continued threat of terrorism, both within the U.S. and abroad, ongoing military actions, and heightened security measures in response to these types of threats may cause significant volatility in the global financial markets and result in loss of life, property damage, business disruption, and reduced economic activity. Some of the assets in our investment portfolio may be adversely affected by declines in the credit and equity markets and reduced economic activity caused by the continued threat of terrorism. Terrorist actions also could disrupt our operations centers in the U.S. or abroad. In addition, the occurrence of terrorist actions could result in higher claims under our insurance policies than anticipated. Beyond obtaining insurance coverage for our facilities, there are few, if any, commercial options through which to transfer the exposure from extreme events

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away from us. We purchase reinsurance protection against catastrophic disaster events, including terrorism. The continued threat of terrorism could result in increased reinsurance prices and reduced insurance coverage and potentially cause us to retain more risk than we otherwise would retain if we were able to obtain reinsurance at lower prices. See "Reinsurance" contained herein in Item 1 for further discussion.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None

ITEM 2. PROPERTIES

As of December 31, 2018, we owned approximately 2.3 million square feet of office space, comprised of five campuses located in Chattanooga, Tennessee; Portland, Maine; Columbia, South Carolina; Baton Rouge, Louisiana; and Dorking in the United Kingdom. In addition, as of December 31, 2018, we leased approximately 0.2 million square feet of office space in Worcester, Massachusetts and approximately 0.7 million square feet in various other locations throughout the United States, the United Kingdom, Ireland, and Poland. All of the properties owned or leased are used by one or more of all five reporting segments, depending on the location. We believe our properties and facilities are suitable and adequate for current operations.

ITEM 3. LEGAL PROCEEDINGS

Refer to Note 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for information on legal proceedings.

ITEM 4. MINE SAFETY DISCLOSURES

Not Applicable

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PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

Common stock of Unum Group is traded on the New York Stock Exchange. The stock symbol is UNM. Quarterly dividends declared and paid per share of common stock are as follows:

2018
4th Quarter	$	0.26
3rd Quarter	0.26
2nd Quarter	0.23
1st Quarter	0.23
2017
4th Quarter	$	0.23
3rd Quarter	0.23
2nd Quarter	0.20
1st Quarter	0.20

Our board of directors has the authority to declare cash dividends on shares of our common stock. In determining dividends, the board takes into account a number of factors including our financial condition and results of operations, regulatory limitations on the payment of dividends from subsidiaries, cash requirements, general economic conditions, and other factors the board may deem relevant.  For information on restrictions relating to our subsidiaries' ability to pay dividends to Unum Group and certain of its intermediate holding company subsidiaries, see "Liquidity and Capital Resources - Cash Available from Subsidiaries" contained herein in Item 7 and Note 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8. For information relating to compensation plans under which Unum Group's equity securities are authorized for issuance, see Item 12 contained herein.

As of February 15, 2019, there were 9,157 registered holders of common stock. 

The following table provides information about our share repurchase activity for the fourth quarter of 2018:

	(a) Total Number of Shares Purchased	(b) Average Price Paid per Share (1)		(c) Total Number of Shares Purchased as Part of Publicly Announced Program (2)	(d) Approximate Dollar Value of Shares that May Yet Be Purchased Under the Program (2)
October 1 - October 31, 2018	438,628	$	35.46	438,628	$	634,410,786
November 1 - November 30, 2018	2,507,394	36.52		2,507,394	542,845,914
December 1 - December 31, 2018	1,258,211	34.08		1,258,211	499,965,321
Total	4,204,233			4,204,233

(1) The average price paid per share excludes the cost of commissions.

(2) In May 2018, our board of directors authorized the repurchase of up to $750 million of Unum Group's common stock through November 24, 2019.

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ITEM 6. SELECTED FINANCIAL DATA

(in millions of dollars, except share data)
	At or for the Year Ended December 31
	2018			2017		2016			2015			2014
Income Statement Data
Revenue
Premium Income	$	8,986.1		$	8,597.1	$	8,357.7		$	8,082.4		$	7,797.2
Net Investment Income	2,453.7			2,451.7		2,459.0			2,481.2			2,492.2
Net Realized Investment Gain (Loss)	(39.5		)	40.3		24.2			(43.8		)	16.1
Other Income	198.2			197.7		205.6			211.5			219.0
Total Revenue	11,598.5			11,286.8		11,046.5			10,731.3			10,524.5
Benefits and Expenses
Benefits and Change in Reserves for Future Benefits1	8,020.4			7,055.7		6,941.8			6,782.8			7,310.8
Commissions	1,108.4			1,060.8		1,026.7			996.3			935.3
Interest and Debt Expense	167.3			159.9		166.0			152.8			167.5
Other Expenses2	1,674.6			1,606.4		1,564.3			1,561.1			1,568.9
Total Benefits and Expenses	10,970.7			9,882.8		9,698.8			9,493.0			9,982.5
Income Before Income Tax	627.8			1,404.0		1,347.7			1,238.3			542.0
Income Tax	104.4			409.8		416.3			371.2			139.9
Net Income	$	523.4		$	994.2	$	931.4		$	867.1		$	402.1
Balance Sheet Data
Assets	$	61,875.6		$	64,013.1	$	61,941.5		$	60,563.6		$	62,422.5
Long-term Debt	$	2,971.3		$	2,738.4	$	2,999.4		$	2,449.4		$	2,601.6
Accumulated Other Comprehensive Income (Loss)	$	(814.2	)	$	127.5	$	(51.0	)	$	16.1		$	166.4
Other Stockholders' Equity	9,436.0			9,447.4		9,019.0			8,647.8			8,355.5
Total Stockholders' Equity	$	8,621.8		$	9,574.9	$	8,968.0		$	8,663.9		$	8,521.9
Per Share Data
Net Income
Basic	$	2.38		$	4.39	$	3.96		$	3.51		$	1.57
Assuming Dilution	$	2.38		$	4.37	$	3.95		$	3.50		$	1.57
Stockholders' Equity	$	40.19		$	43.02	$	39.02		$	35.96		$	33.78
Cash Dividends	$	0.98		$	0.86	$	0.77		$	0.70		$	0.62
Weighted Average Common Shares Outstanding
Basic (000s)	219,635.6			226,492.4		235,445.7			246,986.7			255,525.9
Assuming Dilution (000s)	220,058.6			227,335.2		235,979.2			247,854.7			256,652.8

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¹Includes reserve increases of $750.8 million and $698.2 million in 2018 and 2014, respectively, related to our long-term care closed block business. See Note 6 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion of the 2018 reserve increase.

² Includes the net change in deferred acquisition costs as well as compensation expense and other expenses. Includes $64.4 million in 2014 related to a settlement loss for a pension plan amendment.

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ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The discussion and analysis presented in this section should be read in conjunction with the "Cautionary Statement Regarding Forward-Looking Statements" included below the Table of Contents, "Risk Factors" included in Item 1A, "Selected Financial Data" included in Item 6, and the Consolidated Financial Statements and notes thereto included in Item 8.

Executive Summary

2018 Operating Performance and Capital Management

For 2018, we reported net income of $523.4 million, or $2.38 per diluted common share, compared to net income of $994.2 million, or $4.37 per diluted common share, in 2017. Net income includes net realized investment gains and losses. Included in the 2018 results is a reserve increase related to our long-term care block of business of $750.8 million before tax and $593.1 million after tax, or $2.70 per diluted common share. Excluding these items, after-tax adjusted operating income for 2018 was $1,145.0 million, or $5.20 per diluted common share. Included in the 2017 results are a loss from a guaranty fund assessment related to an unaffiliated insurer that was declared insolvent of $20.6 million before tax and $13.4 million after tax, or $0.06 per diluted common share, a 2017 reserve increase related to unclaimed death benefits of $39.0 million before tax and $25.4 million after tax, or $0.11 per diluted common share, and a net tax benefit related to U.S. tax reform of $31.5 million, or $0.14 per diluted common share. Excluding these items, after-tax adjusted operating income for 2017 was $976.2 million, or $4.29 per diluted common share. See "Long-term Care Reserve Increase," "Unclaimed Death Benefits Reserve Increase," "U.S. Tax Reform," "Reconciliation of Non-GAAP and Other Financial Measures," and "Consolidated Operating Results" contained herein in this Item 7 for further discussion and a reconciliation of these items.

Our Unum US segment reported an increase in adjusted operating income of0.5percent in 2018 compared to 2017, with growth in premium income, partially offset by lower net investment income.Included in adjusted operating income for the fourth quarter of 2017 is a reserve release of $19.5 million in the individual disability product line resulting from our annual review of reserve adequacy, which reflects the recognition of updated morbidity assumptions in our disabled life reserves.The benefit ratio for our Unum US segment for 2018 was 67.2 percent, compared to67.4percent. Unum US salesdecreased1.3percent in2018compared to2017. Overall persistency was consistent with our expectations with favorable persistency in our group product lines and less favorable persistency in our supplemental and voluntary product lines.

Our Unum International segment reported an increase of 2.0 percent in adjusted operating income, as measured in U.S. dollars. Our Unum UK line of business reported a decrease of3.0 percentin adjusted operating income compared to2017, as measured in local currency, due primarily to lower net investment income, partially offset by an increase in premium income. The benefit ratio for our Unum UK line of business was 74.4 percent in both 2018 and 2017. Unum UK sales, as measured in local currency, decreased6.4 percent in 2018 compared to 2017. Persistency was favorable relative to the prior year and is consistent with our expectations. The results of our Unum Poland line of business were not material to our 2018 results of operations.

Our Colonial Life segment reported an increase in adjusted operating income of 3.1 percent in 2018 compared to 2017 due to growth in premium income and net investment income. The 2018 benefit ratio for Colonial Life was 51.4 percent, which was consistent with 2017. Colonial Life sales increased8.0 percent in 2018 compared to 2017. Persistency was unfavorable relative to the prior year but is consistent with our expectations.

Our Closed Block segment reported an increase in adjusted operating income of 1.3 percent in 2018 compared to 2017 due primarily to an increase in net investment income and overall favorable benefits experience, partially offset by lower premium income. Benefits experience for individual disability remains within our range of expectations and was favorable in 2018 compared to 2017. Benefits experience in our long-term care line of business, excluding the reserve increase, was consistent with our expectations.

Although our profit margins continue to be pressured by the impact of the low interest rate environment on our net investment income yields, our invested asset quality remains strong. The net unrealized gain on our fixed maturity securities was $2.7 billion at December 31, 2018, compared to $5.7 billion at December 31, 2017, with the decrease due to higher credit spreads and U.S. Treasury rates during 2018. The earned book yield on our investment portfolio was 5.15 percent for 2018 compared to a yield of 5.23 percent for 2017.

We believe our capital and financial positions are strong. At December 31, 2018, the RBC ratio for our traditional U.S. insurance subsidiaries, calculated on a weighted average basis using the NAIC Company Action Level formula, was

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approximately 370 percent, which is in line with our expectations but lower relative to the prior year as a result of the higher RBC factors adopted by the NAIC in 2018 in response to the lower U.S. statutory income tax rate. During 2018, we repurchased 8.7 million shares of Unum Group common stock under our share repurchase program, at a cost of approximately $351 million. Our weighted average common shares outstanding, assuming dilution, equaled 220.1 million for 2018 compared to 227.3 million for 2017, reflecting our capital management strategy of returning capital to shareholders through repurchases of our common stock. As of December 31, 2018, Unum Group and our intermediate holding companies held fixed maturity securities, short-term investments, and cash of $602 million.

Long-term Care Reserve Increase

Policy reserves for our long-term care block of business are determined using the gross premium valuation method and, prior to the third quarter of 2018, were valued based on assumptions established as of December 31, 2014, the date of our last assumption update under loss recognition. Gross premium valuation assumptions do not change after the date of loss recognition unless reserves are again determined to be deficient. We undertake a review of policy reserve adequacy annually during the fourth quarter of each year, or more frequently if appropriate, using best estimate assumptions as of the date of the review.

During the third quarter of 2018, we completed our annual review of policy reserve adequacy, which incorporated our most recent experience and included a review of all assumptions. The review utilized internal and external data and outside consulting firms for quality assurance and industry benchmarking. Based on our analysis, during the third quarter of 2018, we updated our reserve assumptions and determined that our policy and claim reserves should be increased by $750.8 million, or $593.1 million after-tax, to reflect our current estimate of future benefit obligations. This increase was primarily driven by the update to our liability and interest rate assumptions, particularly claims incidence and claim termination rates, which resulted in an increase to reserves of approximately $2.2 billion. Partially offsetting the increase was the update to our assumptions for premium rate increases which decreased reserves approximately $1.4 billion, resulting in the net increase to reserves of $750.8 million. See "Trends in Key Assumptions" contained herein in the "Critical Accounting Estimates" of this Item 7 for further discussion of the assumptions used in our long-term care reserve update.

2018 and 2016 Acquisitions of Business

In November 2018, we acquired 100 percent of the shares and voting interests in Jaimini Health, Inc. (Jaimini Health), a dental health maintenance organization. The acquisition of Jaimini Health will broaden our employee benefit dental offerings in the U.S., particularly in the state of California and is reported in our Unum US segment.

In October 2018, we acquired 100 percent of the shares and voting interests in Pramerica Zycie TUiR S.A. (which we have subsequently renamed Unum Zycie TUiR S.A. and refer to as Unum Poland), a financial protection benefits provider in Poland. This acquisition will expand our European presence, which we believe to be an attractive market for financial protection benefits.

In January 2018, we acquired 100 percent of the shares and voting interests in Leavelogic, Inc (Leavelogic), a leave management technology provider. The acquisition of Leavelogic will enhance our current leave management offerings by providing tools for employers and employees to better manage the family leave process and is reported in our Unum US segment.

In August 2016, we acquired 100 percent of the shares and voting interests in H&J Capital, L.L.C., parent of Starmount Life Insurance Company and AlwaysCare Benefits (which collectively we refer to as Starmount). Starmount Life Insurance Company is an independent provider of dental and vision insurance in the U.S. workplace, and AlwaysCare Benefits is a nationally licensed, third-party administrator. The acquisition of Starmount broadens our employee benefit offerings in the U.S. Starmount's dental and vision products and new dental and vision products marketed by Unum US are reported in our Unum US segment within our supplemental and voluntary product lines. Colonial Life dental and vision products were introduced in 2018 and are reported in our Colonial Life segment within our accident, sickness, and disability product line.

See Note 13 of the " Notes to Consolidated Financial Statements” contained herein in Item 8 for further details.

Unclaimed Death Benefits (UDB) Reserve Increase

Beginning in 2011, a number of state regulators began requiring insurers to cross-check specified insurance policies with the Social Security Administration’s Death Master File to identify potential matches. If a potential match was identified, insurers were requested to determine if benefits were due, locate beneficiaries, and make payments where appropriate. We initiated this process where requested, and in 2012 we began implementing this process in all states on a forward-looking basis. In addition to

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implementing this on a forward-looking basis, in 2013 we began an initiative to search for potential claims from previous years. During 2013, we completed our assessment of benefits which we estimated would be paid under this initiative, and as such, established additional reserves for payment of these benefits.

Similar to other insurers, we have undergone an examination by a third party acting on behalf of a number of state treasurers concerning our compliance with the unclaimed property laws of the participating states.  In the fourth quarter of 2017, we started the process to reach a Global Resolution Agreement with the third party regarding settlement of the examination, which we finalized in January of 2018. During the fourth quarter of 2017, we established reserves which reflected our estimate of the liability expected to be paid as we execute on the terms of the settlement. Claim reserves were increased $18.5 million for Unum US group life, $8.1 million for Unum US voluntary life, and $12.4 million for Colonial Life voluntary life, for a total reserve increase of $39.0 million before tax and $25.4 million after tax.

U.S. Tax Reform

On December 22, 2017, the U.S. Federal government enacted a tax bill, H.R.1, An Act to Provide Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018, more commonly known as the Tax Cuts and Jobs Act (TCJA). The TCJA, among other things, included a reduction to the U.S. corporate statutory tax rate from 35 percent to 21 percent and a tax on undistributed and previously untaxed foreign earnings and profits (Deemed Repatriation Tax) at reduced rates. As a result of these changes, we recognized a tax benefit of $97.9 million in 2017 related to the revaluation of our net deferred tax liabilities associated with our U.S. operations to the newly enacted U.S. corporate tax rate and a tax expense of $66.4 million resulting from the Deemed Repatriation Tax. See "Regulation" contained herein in Item 1 and Note 7 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further details.

U.K. Referendum

During 2016, the U.K. held a referendum and voted to leave the EU. The U.K. subsequently invoked Article 50 of the Treaty on European Union (EU) and is due to leave the EU on March 29, 2019. We expect to see continued dampening of growth in the U.K. as well as earnings volatility due to the current disruption and uncertainty in the U.K. economy. We may also experience volatility in the fair values of our investments in U.K. and EU-based issuers, but we do not expect a material increase in other-than-temporary impairments or defaults, nor do we believe this volatility will impact our ability to hold these investments. The magnitude and longevity of potential negative economic impacts on our growth will depend on whether an agreement is reached between the U.K. and EU as a result of exit negotiations and, if reached, the nature of the agreement and the resulting response of the U.K. marketplace. There are currently no indications that capital requirements for our U.K. operations will change, but economic conditions may cause volatility in our solvency ratios. Our reported consolidated financial results may continue to be impacted by fluctuations in the British pound sterling to dollar exchange rate. See "Regulation" contained herein in Item 1 and "Unum International Segment" contained herein this Item 7.

Consolidated Company Outlook for 2019

We believe our disciplined approach to providing financial protection products at the workplace puts us in a position of strength as we seek to capitalize on the growing and largely unfilled need for our products and services. We believe the need for our products and services remains strong, and we intend to continue protecting our solid margins and returns through our pricing and risk actions. Our strategy is underpinned by our core values and is centered on market growth through the expansion of our product portfolio, distribution system, and geographic footprint, and enhancing the customer experience through efficiency, simplification, and investment in digital capabilities. 

Our outlook for 2019 is for continued solid premium growth trends in our core businesses, with stable persistency and a disciplined approach to sales growth. We expect to have generally stable benefits experience due to our focus on disciplined pricing, risk selection, and management of renewals. We will maintain our commitment to expense discipline and improving our operational efficiencies.

The low interest rate environment continues to place pressure on our profit margins. Our reported consolidated financial results may also continue to be unfavorably impacted by political and economic uncertainty in the U.K., specifically lower interest rates, wage inflation and employer spending, and claims volatility. We expect our effective tax rate for 2019 to be approximately 20 percent. The reduction in the corporate tax rate resulting from tax reform has improved the statutory earnings and cash generation of our insurance subsidiaries and our capital position remains strong.

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We continue to analyze and employ strategies that we believe will help us navigate the current environment and allow us to maintain solid operating margins and significant financial flexibility to support the needs of our businesses, while also continuing to return capital to our shareholders and exploring merger and acquisition opportunities to enhance our business lines. We have substantial leverage to rising interest rates and an improving economy which generates payroll growth and wage inflation. We believe that consistent operating results, combined with the implementation of strategic initiatives and the effective deployment of capital, will allow us to meet our long-term financial objectives.

Further discussion is included in "Reconciliation of Non-GAAP Financial Measures," "Consolidated Operating Results," "Segment Results," "Investments," and "Liquidity and Capital Resources" contained herein in this Item 7 and in the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Reconciliation of Non-GAAP and Other Financial Measures

We analyze our performance using non-GAAP financial measures. A non-GAAP financial measure is a numerical measure of a company's performance, financial position, or cash flows that excludes or includes amounts that are not normally excluded or included in the most directly comparable measure calculated and presented in accordance with GAAP. The non-GAAP financial measure of "after-tax adjusted operating income" differs from net income as presented in our consolidated operating results and income statements prepared in accordance with GAAP due to the exclusion of net realized investment gains and losses and certain other items as specified in the reconciliations below. We believe after-tax adjusted operating income is a better performance measure and better indicator of the profitability and underlying trends in our business.

Realized investment gains or losses depend on market conditions and do not necessarily relate to decisions regarding the underlying business of our segments. Our investment focus is on investment income to support our insurance liabilities as opposed to the generation of realized investment gains or losses. Although we may experience realized investment gains or losses which will affect future earnings levels, a long-term focus is necessary to maintain profitability over the life of the business since our underlying business is long-term in nature, and we need to earn the interest rates assumed in calculating our liabilities.

We may at other times exclude certain other items from our discussion of financial ratios and metrics in order to enhance the understanding and comparability of our operational performance and the underlying fundamentals. We exclude these items as we believe them to be infrequent or unusual in nature, but this exclusion is not an indication that similar items may not recur and does not replace net income or net loss as a measure of our overall profitability.

See "Executive Summary" contained herein in Item 7 and Notes 6, 7, and 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion regarding the impacts of the long-term care reserve increase, the TCJA, the unclaimed death benefit reserve increase, and the loss from a guaranty fund assessment, respectively.

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A reconciliation of GAAP financial measures to our non-GAAP financial measures is as follows:

	Year Ended December 31
	2018						2017						2016
	(in millions)			per share *			(in millions)			per share *			(in millions)		per share *
Net Income	$	523.4		$	2.38		$	994.2		$	4.37		$	931.4	$	3.95
Excluding:
Net Realized Investment Gain (Loss) (net of tax expense (benefit) of $(11.0); $15.0; $8.4)	(28.5		)	(0.12		)	25.3			0.11			15.8		0.07
Loss from Guaranty Fund Assessment (net of tax benefit of $-; $7.2; $-)	—			—			(13.4		)	(0.06		)	—		—
Unclaimed Death Benefits Reserve Increase (net of tax benefit of $-; $13.6; $-)	—			—			(25.4		)	(0.11		)	—		—
Net Tax Benefit from Impacts of TCJA	—			—			31.5			0.14			—		—
Long-term Care Reserve Increase (net of tax benefit of $157.7; $-; $-)	(593.1		)	(2.70		)	—			—			—		—
After-tax Adjusted Operating Income	$	1,145.0		$	5.20		$	976.2		$	4.29		$	915.6	$	3.88
* Assuming Dilution

We measure and analyze our segment performance on the basis of "adjusted operating revenue" and "adjusted operating income" or "adjusted operating loss", which differ from total revenue and income before income tax as presented in our consolidated statements of income due to the exclusion of net realized investment gains and losses and certain other items as specified in the reconciliations below. These performance measures are in accordance with GAAP guidance for segment reporting, but they should not be viewed as a substitute for total revenue, income before income tax, or net income. 

A reconciliation of total revenue to "adjusted operating revenue" and income before income tax to "adjusted operating income" is as follows:

	Year Ended December 31
	2018			2017			2016
	(in millions of dollars)
Total Revenue	$	11,598.5		$	11,286.8		$	11,046.5
Excluding:
Net Realized Investment Gain (Loss)	(39.5		)	40.3			24.2
Adjusted Operating Revenue	$	11,638.0		$	11,246.5		$	11,022.3
Income Before Income Tax	$	627.8		$	1,404.0		$	1,347.7
Excluding:
Net Realized Investment Gain (Loss)	(39.5		)	40.3			24.2
Loss from Guaranty Fund Assessment	—			(20.6		)	—
Unclaimed Death Benefits Reserve Increase	—			(39.0		)	—
Long-term Care Reserve Increase	(750.8		)	—			—
Adjusted Operating Income	$	1,418.1		$	1,423.3		$	1,323.5

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Critical Accounting Estimates

We prepare our financial statements in accordance with GAAP. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in our financial statements and accompanying notes. Estimates and assumptions could change in the future as more information becomes known, which could impact the amounts reported and disclosed in our financial statements. The accounting estimates deemed to be most critical to our financial position and results of operations are those related to reserves for policy and contract benefits, deferred acquisition costs, valuation of investments, pension and postretirement benefit plans, income taxes, and contingent liabilities. For additional information, refer to our significant accounting policies in Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Reserves for Policy and Contract Benefits

Reserves for policy and contract benefits are our largest liabilities and represent claims that we estimate we will eventually pay to our policyholders. The two primary categories of reserves are policy reserves for claims not yet incurred and claim reserves for claims that have been incurred or are estimated to have been incurred but not yet reported to us. Reserves for policy and contract benefits equaled $43.3 billion and $42.1 billion at December 31, 2018 and 2017, respectively, or approximately 81.3 percent and 77.4 percent of our total liabilities, respectively. Reserves ceded to reinsurers were $7.2 billion at both December 31, 2018 and 2017 and are reported as a reinsurance recoverable in our consolidated balance sheets.

Policy Reserves

Policy reserves are established in the same period we issue a policy and equal the difference between projected future policy benefits and future premiums, allowing a margin for expenses and profit. These reserves relate primarily to our non-interest sensitive products, including our individual disability and voluntary benefits products in our Unum US segment; individual disability and life products in our Unum International segment; disability and cancer and critical illness policies in our Colonial Life segment; and individual disability, long-term care, and other products in our Closed Block segment. The reserves are calculated based on assumptions that were appropriate at the date the policy was issued and are not subsequently modified unless the policy reserves become inadequate (i.e. loss recognition occurs).

• Persistency assumptions are based on our actual historical experience adjusted for future expectations.

• Claim incidence and claim resolution rate assumptions related to mortality and morbidity are based on actual experience or industry standards adjusted as appropriate to reflect our actual experience and future expectations.

• Discount rate assumptions are based on our current and expected net investment returns.

In establishing policy reserves, we use assumptions that reflect our best estimate while considering the potential for adverse variances in actual future experience, which results in a total policy reserve balance that has an embedded reserve for adverse deviation. We do not, however, establish an explicit and separate reserve as a provision for adverse deviation from our assumptions.

We perform loss recognition tests on our policy reserves annually, or more frequently if appropriate, using best estimate assumptions as of the date of the test, without a provision for adverse deviation. We group the policy reserves for each major product line within a segment when we perform the loss recognition tests. If the policy reserves determined using these best estimate assumptions are higher than our existing policy reserves net of any deferred acquisition cost balance, the existing policy reserves are increased or deferred acquisition costs are reduced to immediately recognize the deficiency. Thereafter, the policy reserves for the product line are calculated using the same method we used for the loss recognition testing, referred to as the gross premium valuation method, wherein we use our best estimate as of the gross premium valuation (loss recognition) date rather than the initial policy issue date to determine the expected future claims, commissions, and expenses we will pay and the expected future gross premiums we will receive.

Because the key policy reserve assumptions for policy persistency, mortality and morbidity, and discount rates are all locked in at policy issuance based on assumptions appropriate at that time, policy reserve assumptions are generally not changed due to a change in claim status from active to disabled subsequent to policy issuance.  Depending on the funding mechanism, a full policy reserve is held during disability reflecting continued funding of the full policy reserve during a disability claim, or a fractional policy reserve is held reflecting that the individual policyholder would need to recover before he or she can again generate future claims for a separate occurrence. The policy reserves build up and release over time based on assumptions made at the time of policy issuance such that the reserve is eliminated as policyholders either reach the terminal age for coverage, die, or voluntarily lapse the policy. Policy reserves for Unum US, Unum International, and Colonial Life products are determined

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using the net level premium method as prescribed by GAAP. In applying this method, we use, as applicable by product type, morbidity and mortality incidence rate assumptions, claim resolution rate assumptions, and policy persistency assumptions, among others, to determine our expected future claim payments and expected future premium income. We then apply an interest, or discount, rate to determine the present value of the expected future claims and claim expenses we will pay and the expected future premiums we will receive, with a provision for profit allowed.

Policy reserves for our Closed Block segment include certain older policy forms for individual disability, individual and group long-term care, and certain other products, all of which are no longer actively marketed. The reserves for individual disability and individual and group long-term care are determined using the gross premium valuation method. Key assumptions are persistency, mortality and morbidity, claim incidence, claim resolution rates, commission rates, and maintenance expense rates. For long-term care, premium rate increases are also a key assumption. We apply an interest, or discount, rate to determine the present value of the expected future claims, commissions, and expenses we will pay as well as the expected future premiums we will receive, with no provision for future profit. The interest rate is based on our expected net investment returns on the investment portfolio supporting the reserves for these blocks of business. Under the gross premium valuation method, we do not include an embedded provision for the risk of adverse deviation from these assumptions. Gross premium valuation assumptions do not change after the date of loss recognition unless reserves are again determined to be deficient in the future.

Policy reserves for certain other products, excluding individual disability and individual and group long-term care, which are no longer actively marketed and are reported in our Closed Block segment represent $5.9 billion on a gross basis. We have ceded $5.1 billion of reserves related to the other products, which are primarily comprised of policy reserves, to reinsurers. The ceded reserve balance is reported in our consolidated balance sheets as a reinsurance recoverable. We continue to service a block of group pension products, which we have not ceded, and the policy reserves for these products are based on expected mortality rates and retirement rates. Expected future payments are discounted at interest rates reflecting the anticipated investment returns for the assets supporting the liabilities.

Claim Reserves

Claim reserves are established when a claim is incurred or is estimated to have been incurred but not yet reported (IBNR) to us and, as prescribed by GAAP, equals our long-term best estimate of the present value of the liability for future claim payments and claim adjustment expenses. A claim reserve is based on actual known facts regarding the claim, such as the benefits available under the applicable policy, the covered benefit period, the age, and, as appropriate, the occupation and cause of disability of the claimant, as well as assumptions derived from our actual historical experience and expected future changes in experience for factors such as the claim duration, discount rate, and policy benefit offsets, including those for social security and other government-based welfare benefits. Reserves for IBNR claims, similar to incurred claim reserves, include our assumptions for claim duration and discount rates, but because we do not yet know the facts regarding the specific claims, these reserves are also established based on historical incidence rate assumptions, including claim reporting patterns, the average cost of claims, and the expected volumes of incurred claims. Our incurred claim reserves and IBNR claim reserves do not include any provision for the risk of adverse deviation from our assumptions.

Claim reserves, unlike policy reserves, are subject to revision as current claim experience and projections of future factors affecting claim experience change. Each quarter we review our emerging experience to ensure that our claim reserves are appropriate. If we believe, based on our actual experience and our view of future events, that our long-term assumptions need to be modified, we adjust our reserves accordingly with a charge or credit to our current period income.

Multiple estimation methods exist to establish claim reserve liabilities, with each method having its own advantages and disadvantages. Available reserving methods utilized to calculate claim reserves include the tabular reserve method, the paid loss development method, the incurred loss development method, the count and severity method, and the expected claim cost method. No single method is better than the others in all situations and for all product lines. The estimation methods we have chosen are those that we believe produce the most reliable reserves.

We use a tabular reserve methodology on reported claims for our Unum US group long-term disability and individual disability claims as well as for our Closed Block individual disability and group and individual long-term care claims. Under the tabular reserve methodology, reserves for reported claims are based on certain characteristics of the actual reported claimants, such as age, length of time disabled, and medical diagnosis, as well as assumptions regarding claim duration, discount rate, and policy benefit offsets. We believe the tabular reserve method is the most accurate to calculate long-term liabilities and allows us to use the most available known facts about each claim. IBNR claim reserves for our long-term products are calculated using the count and severity method using historical patterns of the claims to be reported and the associated claim costs. For Unum US group short-term disability products, an estimate of the value of future payments to be made on claims already submitted, as well as on

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IBNR claims, is determined in aggregate using a paid loss development method rather than on the individual claimant basis that we use for reported claims on long-term products. The average length of time between the event triggering a claim under a policy and the final resolution of those claims is much shorter for these products than for our long-term liabilities and results in less estimation variability.

Claim reserves for Unum US group life and accidental death and dismemberment products are related primarily to death claims reported but not yet paid, IBNR death claims, and a liability for waiver of premium benefits. The death claim reserve is based on the actual face amount to be paid, the IBNR reserve is calculated using the paid loss development method, and the waiver of premium benefits reserve is calculated using the tabular reserve methodology.

Claim reserves supporting the group and individual dental and vision products reported in our Unum US and Colonial Life segments have a short claim payout period. As a result, the reserves, which primarily represent IBNR and a small amount of claims pending payment, are calculated using the paid loss development method.

Claim reserves supporting our Unum International segment are calculated using generally the same methodology that we use for Unum US disability and group term life reserves. Claim reserves for our Unum UK group dependent life product are calculated using discounted cash flows, based on our assumptions for claim duration and discount rates. The assumptions used in calculating claim reserves for this segment are based on standard country-specific industry experience, adjusted for our own experience.

The majority of the Colonial Life segment lines of business have short-term benefits, which generally have less estimation variability than our long-term products because of the shorter claim payout period. Our claim reserves for Colonial Life's lines of business are predominantly determined using the incurred loss development method based on our own experience. The incurred loss development method uses the historical patterns of payments by loss date to predict future claim payments for each loss date. Where the incurred loss development method may not be appropriate, we estimate the incurred claims using an expected claim cost per policy or other measure of exposure. The key assumptions for claim reserves for the Colonial Life lines of business are: (1) the timing, rate, and amount of estimated future claim payments; and (2) the estimated expenses associated with the payment of claims.

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The following table displays policy reserves, incurred claim reserves, and IBNR claim reserves by major product line, with the summation of the policy reserves and claim reserves shown both gross and net of the associated reinsurance recoverable. Incurred claim reserves represent the expected benefits payable under each incurred claim, along with other expenses associated with the payment of the claims. IBNR claim reserves include provisions for incurred but not reported claims and a provision for reopened claims for our disability products. The IBNR and reopened claim reserves for our disability products are developed and maintained in aggregate based on historical monitoring. Impacting year over year comparability of policy and claim reserves in the following chart is the 2018 long-term care reserve increase. See "Executive Summary" contained herein in this Item 7 and Note 6 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

(in millions of dollars)	December 31, 2018
	Gross												Total Reinsurance Ceded
	Policy Reserves				Claim Reserves										Total Net
			%		Incurred		IBNR		%		Total
Group Disability	$	—	—	%	$	5,900.0	$	670.8	28.4	%	$	6,570.8	$	71.0	$	6,499.8
Group Life and Accidental Death & Dismemberment	52.9		0.3		750.7		217.8		4.2		1,021.4		7.1		1,014.3
Individual Disability	518.4		2.6		1,357.8		137.1		6.4		2,013.3		217.1		1,796.2
Voluntary Benefits	1,643.9		8.1		49.0		58.1		0.5		1,751.0		27.1		1,723.9
Dental and Vision	—		—		0.1		14.5		0.2		14.6		0.2		14.4
Unum US Segment	2,215.2		11.0		8,057.6		1,098.3		39.7		11,371.1		322.5		11,048.6
Unum International Segment	175.7		0.9		1,838.4		115.0		8.4		2,129.1		84.6		2,044.5
Colonial Life Segment	2,112.5		10.5		292.6		131.4		1.8		2,536.5		8.0		2,528.5
Individual Disability	332.2		1.6		9,085.0		199.6		40.1		9,616.8		1,646.6		7,970.2
Long-term Care	9,463.2		46.9		1,787.6		235.7		8.7		11,486.5		39.9		11,446.6
Other	5,869.5		29.1		187.6		120.2		1.3		6,177.3		5,119.8		1,057.5
Closed Block Segment	15,664.9		77.6		11,060.2		555.5		50.1		27,280.6		6,806.3		20,474.3
Subtotal	$	20,168.3	100.0	%	$	21,248.8	$	1,900.2	100.0	%	43,317.3		7,221.4		36,095.9
Adjustment Related to Unrealized Investment Gains and Losses											3,220.3		261.4		2,958.9
Consolidated											$	46,537.6	$	7,482.8	$	39,054.8

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	December 31, 2017
	Gross												Total Reinsurance Ceded
	Policy Reserves				Claim Reserves										Total Net
			%		Incurred		IBNR		%		Total
Group Disability	$	—	—	%	$	6,047.0	$	624.2	28.7	%	$	6,671.2	$	73.8	$	6,597.4
Group Life and Accidental Death & Dismemberment	54.9		0.3		735.5		208.0		4.1		998.4		5.2		993.2
Individual Disability	533.4		2.8		1,318.0		137.6		6.3		1,989.0		207.5		1,781.5
Voluntary Benefits	1,566.7		8.3		46.7		61.0		0.5		1,674.4		27.3		1,647.1
Dental and Vision	—		—		0.7		11.3		0.1		12.0		0.3		11.7
Unum US Segment	2,155.0		11.4		8,147.9		1,042.1		39.7		11,345.0		314.1		11,030.9
Unum International Segment	18.1		0.1		1,918.3		108.3		8.7		2,044.7		87.0		1,957.7
Colonial Life Segment	1,989.4		10.5		288.3		137.2		1.8		2,414.9		8.5		2,406.4
Individual Disability	418.5		2.2		9,407.4		219.1		41.5		10,045.0		1,619.8		8,425.2
Long-term Care	8,414.3		44.5		1,494.8		150.9		7.1		10,060.0		40.3		10,019.7
Other	5,894.8		31.3		187.3		120.4		1.2		6,202.5		5,090.6		1,111.9
Closed Block Segment	14,727.6		78.0		11,089.5		490.4		49.8		26,307.5		6,750.7		19,556.8
Subtotal	$	18,890.1	100.0	%	$	21,444.0	$	1,778.0	100.0	%	42,112.1		7,160.3		34,951.8
Adjustment Related to Unrealized Investment Gains and Losses											5,094.7		375.8		4,718.9
Consolidated											$	47,206.8	$	7,536.1	$	39,670.7

Key Assumptions

The calculation of policy and claim reserves involves numerous assumptions, but the primary assumptions used to calculate reserves are (1) the discount rate, (2) the claim resolution rate, and (3) the claim incidence rate for policy reserves and IBNR claim reserves. Of these assumptions, our discount rate and claim resolution rate assumptions have historically had the most significant effects on our level of reserves because many of our product lines provide benefit payments over an extended period of time.

1. The discount rate, which is used in calculating both policy reserves and incurred and IBNR claim reserves, is the interest rate that we use to discount future claim payments to determine the present value. A higher discount rate produces a lower reserve. If the discount rate is higher than our future investment returns, our invested assets will not earn enough investment income to support our future claim payments. In this case, the reserves may eventually be insufficient. We set our assumptions based on our current and expected future investment yield of the assets supporting the reserves, considering current and expected future market conditions. If the investment yield on new investments that are purchased differs from the investment yield of the existing investment portfolio, it is likely that the discount rate assumption on claims will be adjusted to reflect the impact of the new investment yield.

2. The claim resolution rate, used for both policy reserves and incurred and IBNR claim reserves, is the probability that a disability or long-term care claim will close due to recovery or death of the insured. It is important because it is used to estimate how long benefits will be paid for a claim. Estimated resolution rates that are set too high will result in reserves that are lower than they need to be to pay the claim benefits over time. Claim resolution assumptions involve many factors, including the cause of disability, the policyholder's age, the type of contractual benefits provided, and the time since initial disability. We primarily use our own claim experience to develop our claim resolution assumptions. These assumptions are established for the

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probability of death and the probability of recovery from disability. Our studies review actual claim resolution experience over a number of years, with more weight placed on our experience in the more recent years. We also consider any expected future changes in claim resolution experience.

3. The incidence rate, used for policy reserves and IBNR claim reserves, is the rate at which new claims are submitted to us. The incidence rate is affected by many factors, including the age of the insured, the insured's occupation or industry, the benefit plan design, and certain external factors such as consumer confidence and levels of unemployment. We establish our incidence assumption using a historical review of actual incidence results along with an outlook of future incidence expectations.

Establishing reserve assumptions is complex and involves many factors. Reserves, particularly for policies offering insurance coverage for long-term disabilities and long-term care, are dependent on numerous assumptions other than just those presented in the preceding discussion. The impact of internal and external events, such as changes in claims operational procedures, economic trends such as the rate of unemployment and the level of consumer confidence, the emergence of new diseases, new trends and developments in medical treatments, and legal trends and legislative changes, including changes to social security and other government-based welfare benefits programs which provide policy benefit offsets, among other factors, will influence claim incidence rates, claim resolution rates, and claim costs. In addition, for policies offering coverage for disability or long-term care at advanced ages, the level and pattern of mortality rates at advanced ages will impact overall benefit costs. Reserve assumptions differ by product line and by policy type within a product line. Additionally, in any period and over time, our actual experience may have a positive or negative variance from our long-term assumptions, either singularly or collectively, and these variances may offset each other. We test the overall adequacy of our reserves using all assumptions and with a long-term view of our expected experience over the life of a block of business rather than test just one or a few assumptions independently that may be aberrant over a short period of time. Therefore, while it is possible to evaluate the sensitivity of overall adequacy results in our reserves based upon a change in each individual assumption, the actual impacts of changes to a variety of underlying assumptions must be considered in the aggregate by product line in order to judge the overall potential implications to reserve adequacy. The following section presents an overview of our trend analysis for key assumptions and the results of variability in our assumptions, in aggregate, for the reserves which we believe are reasonably possible to have a material impact on our future financial results if actual claims yield a materially different amount than what we currently expect and have reserved for, either favorable or unfavorable.

Trends in Key Assumptions

Generally, we do not expect our mortality and morbidity claim incidence trends or our persistency trends to change significantly in the short-term, and to the extent that these trends do change, we expect those changes to be gradual over a longer period of time. We have historically experienced an increase in our group long-term disability morbidity claim incidence trends during and following a recessionary period and believe claim incidence trends may continue to somewhat follow general economic conditions and demographics of the general workforce. 

Claim incidence rates for Unum US group long-term disability were generally consistent in 2018 compared to the prior year.

In 2018, both short-term and long-term interest rates increased. The long-term interest rates supporting the majority of our lines of business remain below historical norms. The assumptions we used to discount reserves during this period were slightly lower for certain of our product lines. Reserve discount rate assumptions for new policies and new claims are periodically adjusted to reflect our current and expected net investment returns. Changes in our average discount rate assumptions tend to occur gradually over a longer period of time because of the long-duration investment portfolios which support the reserves for the majority of our lines of business.

Our claim resolution rate assumption used in determining reserves is our expectation of the resolution rate we will experience over the life of the block of business and will vary from actual experience in any one period, both favorably and unfavorably. Claim resolution rates are very sensitive to operational and environmental changes and have a greater chance of significant variability in a shorter period of time than our other reserve assumptions. These rates are reviewed on a quarterly basis for the death and recovery components separately. Claim resolution rates in our Unum US group long-term disability product line and in our Closed Block individual disability product line have exhibited some variability over the last several years. Relative to the resolution rate we expect to experience over the life of the block of business, actual quarterly rates during 2018 and 2017 have varied between +10 and -13 percent in our Closed Block individual disability line of business. Actual quarterly rates during 2018 and 2017 have varied by +5 and -5 percent in our Unum US group long-term disability line of business. During 2018, claim resolution rates pertaining to overall mortality experience were relatively consistent with the levels of 2017 and 2016. On

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an annual basis for the years 2016 to 2018, our overall claim resolution rates were fairly consistent with or slightly favorable to our long-term assumptions.

We monitor and test our reserves for adequacy relative to all of our assumptions in the aggregate. In our estimation, scenarios based on reasonably possible variations in each of our reserve assumptions, when modeled together in aggregate, could produce potential results as illustrated in the chart below. The major contributor to the variance for both the Unum US group long-term disability line of business and the Closed Block individual disability line of business is the claim resolution rate.

	Potential impact, positive or negative, of variations in reserve assumptions on our December 31, 2018 claim reserve balance
	(in millions of dollars)
Unum US group long-term disability	3.3%	$207
Closed Block individual disability	2.6%	$209

In addition to our Unum US group long-term disability and Closed Block individual disability lines of business, we consider variability in our reserve assumptions related to long-term care policy reserves.  These reserves are held under the gross premium valuation method with assumptions established during the third quarter of 2018, the date of the latest loss recognition. Assumptions for policy reserves do not change after the date of loss recognition unless reserves are again determined to be deficient. As such, positive developments will result in the accumulation of reserve margin, while adverse developments would result in an additional reserve charge.  Policy reserves for long-term care are based upon a number of key assumptions, and each assumption has various factors which may impact the long-term outcome. Key assumptions with respect to morbidity, mortality, claims incidence and resolutions, persistency, interest rates, and future premium rate increases must incorporate extended views of expectations for many years into the future. Reserves are highly sensitive to these estimates.

During the third quarter of 2018, we completed our annual review of policy reserve adequacy for our long-term care line of business, which incorporated our most recent experience and included a review of all assumptions. The review utilized internal and external data and outside consulting firms for quality assurance and industry benchmarking. Based on our analysis, we updated our reserve assumptions as discussed in the following paragraphs. In addition, we have also included a sensitivity analysis for these assumptions for both favorable and unfavorable deviations applied throughout the entire life of the block. This sensitivity analysis was completed as of the date of our assumption update announcement in the third quarter of 2018 and will not be updated unless reserves are again determined to be deficient in the future.

• We updated our active policy termination assumptions, which are affected by both policyholder mortality and lapses. We aligned our mortality assumptions with industry data based on a 2012 individual annuitant mortality industry table, adjusted for our experience in earlier policy durations. We also lowered our lapse assumptions for individual policies based on emerging company experience, which resulted in an ultimate lapse rate of 0.25 percent. A six percent unfavorable change in the active policy termination assumption would result in approximately a $330 million decrease to reserve margin and a six percent favorable change would result in approximately a $320 million increase to reserve margin.

• We updated our claims incidence assumptions to consider both the elevated claim levels that we have recently experienced as well as longer term experience based on our analysis of numerous claim factors, including variations by age, gender, product, premium funding method, and other factors. A 2.5 percent unfavorable change in the claim incidence assumption would result in approximately a $290 million decrease to reserve margin and a 2.5 percent favorable change would result in approximately a $300 million increase to reserve margin.

• We updated our claim termination assumptions, which are primarily affected by the death, and to a lesser extent, the recovery of the insured to largely reflect our experience. A three percent unfavorable change in the claim termination assumption would result in approximately a $370 million decrease to reserve margin and a three percent favorable change would result in approximately a $360 million increase to reserve margin.

• We have observed morbidity improvement in our own claims experience over a ten year period of approximately three percent per year, normalized for variables such as age and claim type. However, we believe that a longer-term view is the best way to evaluate this type of improvement. Accordingly, we updated our morbidity assumptions to reflect minor improvement, one percent per year, including a partially offsetting assumption of 0.6 percent per year mortality improvement. If no improvement occurs in the morbidity and mortality assumptions, reserve margin would decrease by approximately $1 billion. If a three percent per year improvement in the morbidity and mortality assumptions occurs, reserve margin would increase by approximately $1.6 billion.

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• We updated our premium rate increase assumptions to reflect both our estimate of previously filed rate increases, informed by our historical approval rates, and our anticipated future rate filings. The impact of the update to the premium rate increase assumptions resulted in approximately a $1.4 billion decrease to reserves, of which approximately $700 million relates to currently outstanding requests pending approval with the remaining $700 million related to future rate increase submissions, with a focus on group policies, that will be completed and filed during the next several quarters. A ten percent change in the premium rate increase success rate assumption would result in an approximately $140 million change in reserve margin depending on whether the change was favorable or unfavorable.

• We updated our discount rate assumption to reflect our expectation for the low interest rate environment to persist and our expected impact on future long-term care new money yield rates. Our updated expectation for long-term care new money yield rates assumes a rate of 5.5 percent through 2021 and then a gradual increase to 6.25 percent by 2025, when we assume no further increase. A 0.25 percent change in the new money yield rate assumption would result in an approximately $250 million change in reserve margin depending on whether the change was favorable or unfavorable. Alternatively, a 0.25 percent change in the overall assumed discount rate, which includes the new money yield rate assumption, would impact the reserve margin within an approximate range of $450 million to $500 million, assuming all other factors held constant.

Key assumptions and related impacts are also heavily interrelated in both their outcome and in their effects on reserves. For example, changes in the view of morbidity and mortality might be mitigated by either potential future premium rate increases and/or morbidity improvements due to general improvement in health and/or medical breakthroughs. There is potentially a wide range of outcomes for each assumption and in totality.

We believe that these ranges provide a reasonable estimate of the possible changes in reserve balances for those product lines where we believe it is possible that variability in the assumptions, in the aggregate, could result in a material impact on our reserve levels, but we record our reserves based on our long-term best estimate. Because these product lines have long-term claim payout periods, there is a greater potential for significant variability in claim costs, either positive or negative. We closely monitor emerging experience and use these results to inform our view of long-term assumptions.

Deferred Acquisition Costs (DAC)

We defer incremental direct costs associated with the successful acquisition of new or renewal insurance contracts and amortize these costs over the life of the related policies. Deferred costs include certain commissions, other agency compensation, selection and policy issue expenses, and field expenses. Acquisition costs that do not vary with the production of new business, such as commissions on group products which are generally level throughout the life of the policy, are excluded from deferral.

Approximately 89.4 percent of our DAC relates to non-interest sensitive products, and we amortize DAC for these products in proportion to the premium income we expect to receive over the life of the policies. DAC related to interest sensitive policies is amortized over the lives of the policies in relation to the present value of estimated gross profits from surrender charges, mortality margins, investment returns, and expense margins. Key assumptions used in developing the future amortization of DAC are persistency, premium income, and for our interest sensitive products, mortality margins and investment returns.  We use our own historical experience and expectation of the future performance of our businesses in determining our assumptions.  For non-interest sensitive products, the estimated premium income in the early years of the amortization period is generally higher than in the later years due to the anticipated cumulative effect of policy persistency in the early years, which results in a greater proportion of the costs being amortized in the early years of the life of the policy.  During 2018, our key assumptions used to develop the future amortization of acquisition costs deferred during 2018 did not change materially from those used in 2017.  Generally, we do not expect our key assumptions to change significantly in the short-term, and to the extent that these trends do change, we expect those changes to be gradual over a longer period of time.

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The following are our current assumptions regarding the length of our amortization periods, the approximate DAC balance that remains at the end of years 3, 10, and 15 as a percentage of the cost initially deferred, and our DAC balances as of December 31, 2018 and 2017.

		Balance Remaining as a %			DAC Balances
	Amortization	of Initial Deferral			at December 31
	Period	Year 3	Year 10	Year 15	2018		2017
					(in millions of dollars)
Unum US
Group Disability	6	26%	0%	0%	$	100.3	$	96.8
Group Life and Accidental Death & Dismemberment	6	28%	0%	0%	80.0		77.7
Supplemental and Voluntary:
Individual Disability	20	71%	47%	20%	430.8		431.3
Voluntary Benefits	20	54%	19%	7%	619.7		596.2
Dental and Vision	4	29%	0%	0%	8.6		3.4
Unum International
Group Long-term Disability	3	0%	0%	0%	2.4		3.2
Group Life	3	0%	0%	0%	1.1		1.3
Supplemental	21	58%	14%	4%	16.5		16.8
Colonial Life
Accident, Sickness, and Disability	15	44%	11%	1%	530.1		494.0
Life	25	67%	29%	13%	293.9		252.5
Cancer and Critical Illness	19	57%	25%	10%	226.0		211.4
Totals					$	2,309.4	$	2,184.6

Amortization of DAC is adjusted to reflect actual experience for assumptions which deviate compared to the anticipated experience. Any deviations from projections may result in a change to the rate of amortization in the period such events occur. As an example, for our non-interest sensitive products, we may experience accelerated amortization if policies terminate earlier than projected, or we may experience a slower rate of amortization if policies persist longer than projected. Our actual experience has not varied materially from our assumptions during the last three years.

See Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion of our DAC accounting policy.

Fair Value of Investments

All of our fixed maturity securities, which are classified as available-for-sale, and all our unrestricted equity securities are reported at fair value. Our derivative financial instruments, including certain derivative instruments embedded in other contracts, are reported as either assets or liabilities and measured at fair value. We report our investments in private equity partnerships at our share of the partnerships' net asset value per share or its equivalent (NAV), as a practical expedient for fair value.

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date and therefore represents an exit price, not an entry price. The exit price objective applies regardless of our intent and/or ability to sell the asset or transfer the liability at the measurement date. We generally use valuation techniques consistent with the market approach, and to a lesser extent, the income approach. The market approach uses prices and other relevant information from market transactions involving identical or comparable assets or liabilities and the income approach converts future amounts, such as cash flows or earnings, to a single present amount, or a discounted amount. We believe the market approach valuation technique provides more observable data than the income approach, considering the types of investments we hold.

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The degree of judgment utilized in measuring the fair value of financial instruments generally correlates to the level of pricing observability. Financial instruments with readily available active quoted prices or for which fair value can be measured from actively quoted prices in active markets generally have more pricing observability and less judgment utilized in measuring fair value. The market sources from which we obtain or derive the fair values of our assets and liabilities carried at market value include quoted market prices for actual trades, price quotes from third party pricing vendors, price quotes we obtain from outside brokers, matrix pricing, discounted cash flow, and observable prices for similar publicly traded or privately traded issues that incorporate the credit quality and industry sector of the issuer. Our fair value measurements could differ significantly based on the valuation technique and available inputs.

Inputs to valuation techniques refer broadly to the assumptions that market participants use in pricing assets or liabilities, including assumptions about risk, for example, the risk inherent in a particular valuation technique used to measure fair value and/or the risk inherent in the inputs to the valuation technique. We use observable and unobservable inputs in measuring the fair value of our financial instruments. Observable inputs are inputs that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources. Unobservable inputs are inputs that reflect our own assumptions about the assumptions market participants would use in pricing the asset or liability developed based on the best information available in the circumstances.

Certain of our investments do not have readily determinable market prices and/or observable inputs or may at times be affected by the lack of market liquidity. For these securities, we use internally prepared valuations combining matrix pricing with vendor purchased software programs, including valuations based on estimates of future profitability, to estimate the fair value. Additionally, we may obtain prices from independent third-party brokers to aid in establishing valuations for certain of these securities. Key assumptions used by us to determine fair value for these securities include risk-free interest rates, risk premiums, performance of underlying collateral (if any), and other factors involving significant assumptions which may or may not reflect those of an active market.

As of December 31, 2018, the key assumptions we generally used to estimate the fair value of these types of securities included those listed below. Where appropriate, we have noted the assumption used for the prior period as well as the reason for the change.

• Risk-free interest rates of 2.51 percent for five-year maturities to 3.02 percent for 30-year maturities were derived from the December 31, 2018 yield curve for U.S. Treasury Bonds with similar maturities. This compares to interest rates of 2.21 percent for five-year maturities to 2.74 percent for 30-year maturities used at December 31, 2017.

• Baa corporate bond spread adjustments ranging from 1.23 percent to 2.68 percent were added to the risk-free rate to reflect additional credit risk and the lack of liquidity. We used spread adjustments ranging from 0.83 percent to 1.97 percent at December 31, 2017. The changes were based on observable market spreads. Newly issued private placement securities have historically offered yield premiums higher than a similar interest rate spread on comparable newly issued public securities.

• Additional basis points were added as deemed appropriate for foreign investments, certain industries, and individual securities in certain industries that are considered to be of greater risk.

As of December 31, 2018, approximately 11.7 percent of our fixed maturity securities were categorized as Level 1, 84.5 percent as Level 2, and 3.8 percent as Level 3. Level 1 is the highest category of the three-level fair value hierarchy classification wherein inputs are unadjusted and represent quoted prices in active markets for identical assets or liabilities. The Level 2 category includes assets or liabilities valued using inputs (other than those included in the Level 1 category) that are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument's anticipated life. The Level 3 category is the lowest category of the fair value hierarchy and reflects the judgment of management regarding what market participants would use in pricing assets or liabilities at the measurement date using unobservable inputs to extrapolate an estimated fair value.

Rapidly changing credit and equity market conditions can materially impact the valuation of securities, and the period to period changes in value can vary significantly.

See Note 2 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

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Investment Impairments

One of the significant estimates related to investments is our impairment valuation. In determining when a decline in fair value below amortized cost of a fixed maturity security is other than temporary, we evaluate the following factors:

• Whether we expect to recover the entire amortized cost basis of the security

• Whether we intend to sell the security or will be required to sell the security before the recovery of its amortized cost basis

• Whether the security is current as to principal and interest payments

• The significance of the decline in value

• The time period during which there has been a significant decline in value

• Current and future business prospects and trends of earnings

• The valuation of the security’s underlying collateral

• Relevant industry conditions and trends relative to their historical cycles

• Market conditions

• Rating agency and governmental actions

• Bid and offering prices and the level of trading activity

• Adverse changes in estimated cash flows for securitized investments

• Changes in fair value subsequent to the balance sheet date

• Any other key measures for the related security

We evaluate available information, including the factors noted above, both positive and negative, in reaching our conclusions. In particular, we also consider the strength of the issuer’s balance sheet, its debt obligations and near term funding requirements, cash flow and liquidity, the profitability of its core businesses, the availability of marketable assets which could be sold to increase liquidity, its industry fundamentals and regulatory environment, and its access to capital markets. Although all available and applicable factors are considered in our analysis, our expectation of recovering the entire amortized cost basis of the security, whether we intend to sell the security, whether it is more likely than not we will be required to sell the security before recovery of its amortized cost, and whether the security is current on principal and interest payments are the most critical factors in determining whether impairments are other than temporary. The significance of the decline in value and the length of time during which there has been a significant decline are also important factors, but we generally do not record an impairment loss based solely on these two factors, since often other more relevant factors will impact our evaluation of a security.

While determining other-than-temporary impairments is a judgmental area, we utilize a formal, well-defined, and disciplined process to monitor and evaluate our fixed income investment portfolio, supported by issuer specific research and documentation as of the end of each period. The process results in a thorough evaluation of problem investments and the recording of losses on a timely basis for investments determined to have an other-than-temporary impairment.

We use a comprehensive rating system to evaluate the investment and credit risk of our mortgage loans and to identify specific properties for inspection and reevaluation. Mortgage loans are considered impaired when, based on current information and events, it is probable that we will be unable to collect all amounts due according to the contractual terms of the loan agreement. We establish an allowance for probable losses on mortgage loans based on a review of individual loans, considering the value of the underlying collateral, the value of which is periodically assessed. Mortgage loans are not reported at fair value in our consolidated balance sheets unless the mortgage loan is considered impaired, in which case the impairment is recognized as a realized investment loss in our consolidated statements of income.

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There are a number of significant risks inherent in the process of monitoring our investments for impairments and determining when and if an impairment is other than temporary. These risks and uncertainties include the following possibilities:

• The assessment of a borrower's ability to meet its contractual obligations will change.

• The economic outlook, either domestic or foreign, may be less favorable or may have a more significant impact on the borrower than anticipated, and as such, the investment may not recover in value.

• New information may become available concerning the security, such as disclosure of accounting irregularities, fraud, or corporate governance issues.

• Significant changes in credit spreads may occur in the related industry.

• Significant increases in interest rates may occur and may not return to levels similar to when securities were initially purchased.

• Adverse rating agency actions may occur.