Segment Information

We have three principal operating business segments: Unum US, Unum UK, and Colonial Life. Our other segments are the Closed Block and the Corporate segments.

The 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, which are comprised of individual disability and voluntary benefits products. These products are marketed through our field sales personnel who work in conjunction with independent brokers and consultants.

The Unum UK segment includes insurance for group long-term disability, group life, and supplemental lines of business, which include individual disability and critical illness products. Unum UK's products are sold primarily in the United Kingdom through field sales personnel and independent brokers and consultants.

The Colonial Life segment includes insurance for accident, sickness, and disability products, life products, and cancer and critical illness products marketed to employees at the workplace through an independent contractor agency sales force and brokers.

The Closed Block segment consists of individual disability, group and individual long-term care, and other insurance products no longer actively marketed. The individual disability line of business in this segment generally consists of policies we sold prior to the mid-1990s and entirely discontinued selling in 2004, other than update features contractually allowable on existing policies. We discontinued offering individual long-term care in 2009 and group long-term care in 2012. Other insurance products include group pension, individual life and corporate-owned life insurance, reinsurance pools and management operations, and other miscellaneous product lines.

The 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.

We measure and analyze our segment 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 measures of "operating revenue" and "operating income" or "operating loss" 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, non-operating retirement-related gains or losses, and certain other items as specified in the reconciliations below. We believe operating revenue and operating income or loss are better performance measures and better indicators of the revenue and 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.

The amortization of prior period actuarial gains or losses, a component of the net periodic benefit cost for our pensions and other postretirement benefit plans, is driven by market performance as well as plan amendments and is not indicative of the operational results of our businesses. We believe that excluding the amortization of prior period gains or losses, as well as the settlement loss from our 2014 pension plan amendment, from operating income or loss provides investors with additional information for comparison and analysis of our operating results. Although we manage our non-operating retirement-related gains or losses separately from the operational performance of our business, these gains or losses impact the overall profitability of our company and have historically increased or decreased over time, depending on plan amendments and market conditions and the resulting impact on the actuarial gains or losses in our pensions and other postretirement benefit plans.

We believe that excluding the 2014 costs related to the early retirement of debt is appropriate because in conjunction with the debt redemption, we recognized in realized investment gains and losses a deferred gain from previously terminated derivatives which were associated with the hedge of the debt. The amount recognized as a realized investment gain, which basically offsets the cost of the debt redemption, is also excluded from our non-GAAP financial measures since we analyze our performance excluding amounts reported as realized investment gains or losses. We believe it provides investors with a more realistic view of our overall profitability if we are consistent in excluding both the cost of the debt retirement as well as the gain on the hedge of the debt.

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, 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.

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



	Year Ended December 31
	2014			2013			2012
	(in millions of dollars)
Operating Revenue	$	10,493.6		$	10,347.0		$	10,459.2
Net Realized Investment Gain	16.1			6.8			56.2
Total Revenue	$	10,509.7		$	10,353.8		$	10,515.4

Operating Income	$	1,292.5		$	1,241.8		$	1,239.7
Net Realized Investment Gain	16.1			6.8			56.2
Non-operating Retirement-related Loss	(70.0		)	(32.9		)	(46.4		)
Costs Related to Early Retirement of Debt for Corporate	(13.2		)	—			—
Long-term Care Reserve Increase for Closed Block	(698.2		)	—			—
Unclaimed Death Benefits Reserve Increase for Unum US	—			(75.4		)	—
Unclaimed Death Benefits Reserve Increase for Colonial Life	—			(20.1		)	—
Group Life Waiver of Premium Benefit Reserve Reduction for Unum US	—			85.0			—
Income Before Income Tax	$	527.2		$	1,205.2		$	1,249.5

Premium income by major line of business within each of our segments is presented as follows:



	Year Ended December 31
	2014		2013		2012
	(in millions of dollars)
Unum US
Group Disability
Group Long-term Disability	$	1,553.5	$	1,553.9	$	1,578.8
Group Short-term Disability	558.1		519.6		476.7
Group Life and Accidental Death & Dismemberment
Group Life	1,262.3		1,213.9		1,182.1
Accidental Death & Dismemberment	125.9		121.6		115.3
Supplemental and Voluntary
Individual Disability	466.1		465.3		477.6
Voluntary Benefits	693.8		642.8		626.0
	4,659.7		4,517.1		4,456.5
Unum UK
Group Long-term Disability	418.9		389.9		409.7
Group Life	133.2		106.4		221.3
Supplemental	55.1		60.3		63.6
	607.2		556.6		694.6
Colonial Life
Accident, Sickness, and Disability	759.8		738.7		724.5
Life	231.8		221.1		209.7
Cancer and Critical Illness	282.1		272.4		260.3
	1,273.7		1,232.2		1,194.5
Closed Block
Individual Disability	624.8		687.5		736.4
Long-term Care	630.9		630.6		631.9
All Other	0.9		0.7		2.2
	1,256.6		1,318.8		1,370.5
Total	$	7,797.2	$	7,624.7	$	7,716.1

Selected operating statement data by segment is presented as follows:



	Unum US		Unum UK		Colonial Life		Closed Block		Corporate			Total
	(in millions of dollars)
Year Ended December 31, 2014

Premium Income	$	4,659.7	$	607.2	$	1,273.7	$	1,256.6	$	—		$	7,797.2
Net Investment Income	890.3		151.0		146.7		1,284.1		5.3			2,477.4
Other Income	122.1		—		0.1		91.8		5.0			219.0
Operating Revenue	$	5,672.1	$	758.2	$	1,420.5	$	2,632.5	$	10.3		$	10,493.6

Operating Income (Loss)	$	856.3	$	147.8	$	300.2	$	122.6	$	(134.4	)	$	1,292.5
Interest and Debt Expense Excluding Costs Related to Early Retirement of Debt	$	—	$	—	$	—	$	7.3	$	147.0		$	154.3
Depreciation and Amortization	$	314.2	$	19.2	$	194.1	$	5.9	$	1.0		$	534.4

Year Ended December 31, 2013

Premium Income	$	4,517.1	$	556.6	$	1,232.2	$	1,318.8	$	—		$	7,624.7
Net Investment Income	929.6		148.5		145.4		1,272.3		(3.7		)	2,492.1
Other Income	128.3		0.1		0.2		93.9		7.7			230.2
Operating Revenue	$	5,575.0	$	705.2	$	1,377.8	$	2,685.0	$	4.0		$	10,347.0

Operating Income (Loss)	$	859.0	$	132.0	$	284.9	$	109.4	$	(143.5	)	$	1,241.8
Interest and Debt Expense	$	0.1	$	—	$	—	$	8.4	$	140.9		$	149.4
Depreciation and Amortization	$	292.5	$	22.5	$	188.7	$	5.2	$	0.9		$	509.8

Year Ended December 31, 2012

Premium Income	$	4,456.5	$	694.6	$	1,194.5	$	1,370.5	$	—		$	7,716.1
Net Investment Income	952.3		170.8		138.6		1,230.5		23.0			2,515.2
Other Income	124.6		0.1		0.3		100.1		2.8			227.9
Operating Revenue	$	5,533.4	$	865.5	$	1,333.4	$	2,701.1	$	25.8		$	10,459.2

Operating Income (Loss)	$	847.1	$	131.3	$	274.3	$	95.5	$	(108.5	)	$	1,239.7
Interest and Debt Expense	$	1.1	$	—	$	—	$	10.4	$	133.9		$	145.4
Depreciation and Amortization	$	255.6	$	27.2	$	181.0	$	3.9	$	0.8		$	468.5

The following table provides the changes in deferred acquisition costs by segment:



							Colonial
	Unum US			Unum UK			Life			Total
	(in millions of dollars)
Year Ended December 31, 2014
Beginning of Year	$	1,051.5		$	34.3		$	743.4		$	1,829.2
Capitalization	292.7			10.5			220.8			524.0
Amortization	(248.1		)	(12.5		)	(180.2		)	(440.8		)
Adjustment Related to Unrealized Investment Gains	0.4			—			(9.6		)	(9.2		)
Foreign Currency	—			(1.9		)	—			(1.9		)
End of Year	$	1,096.5		$	30.4		$	774.4		$	1,901.3

Year Ended December 31, 2013
Beginning of Year	$	1,024.3		$	38.8		$	692.4		$	1,755.5
Capitalization	252.0			9.8			205.0			466.8
Amortization	(230.0		)	(14.7		)	(174.2		)	(418.9		)
Adjustment Related to Unrealized Investment Losses	5.2			—			20.2			25.4
Foreign Currency	—			0.4			—			0.4
End of Year	$	1,051.5		$	34.3		$	743.4		$	1,829.2

Year Ended December 31, 2012
Beginning of Year	$	971.8		$	40.9		$	664.4		$	1,677.1
Capitalization	249.2			11.8			206.3			467.3
Amortization	(196.5		)	(15.7		)	(166.5		)	(378.7		)
Adjustment Related to Unrealized Investment Gains	(0.2		)	—			(11.8		)	(12.0		)
Foreign Currency	—			1.8			—			1.8
End of Year	$	1,024.3		$	38.8		$	692.4		$	1,755.5

Assets by segment are as follows:



	December 31
	2014		2013
	(in millions of dollars)
Unum US	$	18,676.5	$	18,384.3
Unum UK	3,702.5		3,654.1
Colonial Life	3,692.2		3,482.9
Closed Block	33,960.2		31,564.2
Corporate	2,465.7		2,318.1
Total Assets	$	62,497.1	$	59,403.6

Revenue is primarily derived from sources in the United States and the United Kingdom. There are no material revenues or assets attributable to foreign operations other than those reported in our Unum UK segment.

We report goodwill in our Unum US segment and in our Unum UK segment, which are the segments expected to benefit from the originating business combinations. At December 31, 2014 and 2013, goodwill was $198.7 million and $200.9 million, with $187.6 million and $189.0 million, respectively, attributable to Unum US and the remainder attributable to Unum UK.

Stockholders' equity is allocated to the operating segments on the basis of an internal allocation formula that reflects the volume and risk components of each operating segment's business and aligns allocated equity with our target capital levels for regulatory and rating agency purposes. We modify this formula periodically to recognize changes in the views of capital requirements.