RESERVE FOR LOSSES AND LOSS EXPENSES

12 Months Ended

Dec. 31, 2017

Insurance Loss Reserves [Abstract]

RESERVE FOR LOSSES AND LOSS EXPENSES

Reserving Methodology

The reserving process begins with the collection and analysis of paid and incurred claim data for each of the Company's segments. The segmental data is disaggregated by reserving class and further disaggregated by underwriting year (i.e. the year in which the contract generating the premium and losses incepted). Underwriting year information is used to analyze business and subsequently allocate reserves to the respective accident years. Reserve classes are selected to ensure that the underlying contracts have homogeneous loss development characteristics, while remaining large enough to make the estimation of trends credible. This data, in addition to industry benchmarks, serves as a key input to many of the methods employed by the Company's actuaries. The relative weights assigned to its own historical loss data versus industry data vary according to the length of the development profile for the reserving class being evaluated. (See 'Net Incurred and Paid Claims Development Tables By Accident Year' below for further details by reserve class.)

The following tables reconcile reserve classes to the lines of business categories and the expected claim tails:

Insurance Segment
		Reported Lines of Business
Reserve Classes	Tail	Property	Marine	Terrorism	Aviation	Credit and Political Risk	Professional Lines	Liability	Accident and Health	Discontinued lines - Novae
Property and Other	Short	X		X					X	X
Marine	Short		X
Aviation	Short				X
Credit and Political Risk	Medium					X
Professional Lines	Medium						X			X
Liability	Long							X		X

Reinsurance Segment
		Reported Lines of Business
Reserve Classes	Tail	Catastrophe	Property	Credit and Surety	Professional Lines	Motor	Liability	Engineering	Agriculture	Marine and Other	Discontinued lines - Novae
Property and Other	Short	X	X					X	X	X	X
Credit and Surety	Medium			X
Professional Lines	Medium				X
Motor	Long					X					X
Liability	Long						X				X

The Company has presented separate loss development tables for the Aviabel and Novae business prospectively from the date of acquisition.

Multiple actuarial methods are available to estimate ultimate losses. Each method has its own assumptions and its own advantages and disadvantages, with no single estimation method being better than the others in all situations and no one set of assumption variables being meaningful for all reserve classes. The relative strengths and weaknesses of the particular estimation methods when applied to a particular group of claims can also change over time.

The following is a brief description of the reserve estimation methods commonly employed by the Company's actuaries:

• Expected Loss Ratio Method ("ELR Method"): This method estimates ultimate losses for an accident year or underwriting year by applying an expected loss ratio to the earned or written premium for that year. Generally, expected loss ratios are based on one or more of (a) an analysis of historical loss experience to date, (b) pricing information and (c) industry data, adjusted as appropriate, to reflect changes in rates and terms and conditions. This method is insensitive to actual incurred losses for the accident year or underwriting year in question and is, therefore, often useful in the early stages of development when very few losses have been incurred. Conversely, the lack of sensitivity to incurred/paid losses for the accident year or underwriting year in question means that this method is usually inappropriate in later stages of an accident year or underwriting year’s development.

• Loss Development Method (also referred to as the Chain Ladder Method or Link Ratio Method): This method assumes that the losses incurred/paid for each accident year or underwriting year at a particular development stage follow a relatively similar pattern. It assumes that on average, every accident year or underwriting year will display the same percentage of ultimate losses incurred/paid at the same point in time after the inception of that year. The percentages incurred/paid are established for each development stage (e.g. 12 months, 24 months, etc.) after examining historical averages from historical loss development data and/or external industry benchmark information. Ultimate losses are then estimated by multiplying the actual incurred/paid losses by the reciprocal of the established incurred/paid percentage. The strengths of this method are that it reacts to loss emergence/payments and that it makes full use of historical claim emergence/payment experience. However, this method has weaknesses when the underlying assumption of stable loss development/payment patterns is not valid. This could be the consequence of changes in business mix, claim inflation trends or claim reporting practices and/or the presence of large claims, amongst other things. Furthermore, this method tends to produce volatile estimates of ultimate losses where there is volatility in the underlying incurred/paid patterns. In particular, where the expected percentage of incurred/paid losses is low, small deviations between actual and expected claims can lead to very volatile estimates of ultimate losses. As a result, this method is often unsuitable at early development stages for an accident year or underwriting year.

• Bornhuetter-Ferguson Method ("BF Method"): This method can be seen as a combination of the ELR and Loss Development Methods, under which the Loss Development Method is given progressively more weight as an accident year or underwriting year matures. The main advantage of the BF Method is that it provides a more stable estimate of ultimate losses than the Loss Development Method at earlier stages of development, while remaining more sensitive to emerging loss development than the ELR Method. In addition, the BF Method allows for the incorporation of external market information through the use of expected loss ratios, whereas the Loss Development Method does not incorporate such information.

As part of the loss reserve review process, the Company's actuaries employ the estimation method(s) that they believe will produce the most reliable estimate of ultimate losses, at that particular evaluation date, for each reserve class and accident year or underwriting year combination. Often, this is a blend (i.e. weighted average) of the results of two or more appropriate actuarial methods. These ultimate loss estimates are generally utilized to evaluate the adequacy of ultimate loss estimates for previous accident or underwriting years, as established in the prior reporting period. For the initial estimate of the current accident or underwriting year, the available claim data is typically insufficient to produce a reliable estimate of ultimate losses. As a result, initial estimates for an accident or underwriting year are generally based on the ELR Method for longer tailed lines and a BF Method for shorter tailed lines. The initial ELR for each reserve class is established collaboratively by actuaries, underwriters and management at the start of the year as part of the planning process, taking into consideration prior accident years’ or underwriting years' experience and industry benchmarks, adjusted after considering factors such as exposure trends, rate differences, changes in contract terms and conditions, business mix changes and other known differences between the current year and prior accident or underwriting years. The initial expected loss ratios for a given accident or underwriting year may be modified over time if the underlying assumptions, such as loss development or premium rate changes, differ from the original assumptions.

The use of the above actuarial methods requires the Company to make certain explicit assumptions, the most significant of which are: (1) expected loss ratios and (2) loss development patterns.

In earlier years, significant reliance was placed on industry benchmarks in establishing expected loss ratios and loss development patterns. Over time, more reliance has been placed on historical loss experience in establishing these ratios and patterns where the Company believes the weight of its own actual experience has become sufficiently credible for consideration. In establishing expected loss ratios for the insurance segment, consideration is given to a number of other factors, including exposure trends, rate adequacy on new and renewal business, ceded reinsurance costs, changes in claims emergence and underwriters’ view of terms and conditions in the market environment. For the reinsurance segment, expected loss ratios are based on a contract-by-contract review, which considers information provided by clients together with estimates provided by underwriters and actuaries about the impact of changes in pricing, terms and conditions and coverage. Market experience of some classes of business as compiled and analyzed by an independent actuarial firm has also been considered, as appropriate. The weight given to experience differs for each of the three claim tails.

Short-tail business generally includes exposures for which losses are usually known and paid within a relatively short period of time after the underlying loss event has occurred. The majority of development for an accident year or underwriting year is expected to be recognized in the subsequent one to three years. The key actuarial assumptions for short-tail business in early accident years were primarily developed with reference to industry benchmarks for both expected loss ratios and loss development patterns. As the Company's own historical loss experience amassed, it gained credibility and became relevant for consideration in establishing these key actuarial assumptions. As a result, the Company gradually increased the weighting assigned to its own historical experience in selecting the expected loss ratios and loss development patterns utilized to establish estimates of ultimate losses for an accident year. Due to the relatively short reporting and settlement patterns for short-tail business, more weight is generally placed upon experience-based methods and other qualitative considerations in establishing reserves for both recent and more mature accident years.

Medium-tail business generally has claim reporting and settlement periods longer than those of short-tail reserve classes. For the Company's earliest accident and underwriting years, initial key actuarial expected loss ratio and loss development assumptions were established utilizing industry benchmarks. Due to the longer claim tail, the length of time required to develop its own credible loss history for use in the reserve process is greater for medium-tail business than for short-tail business. As a result, the number of years where the Company has relied heavily on industry benchmarks to establish its key actuarial assumptions is greater for medium-tail business.

The claim tails for long-tail business, in contrast to short and medium-tail business, is expected to be notably longer, as claims are often reported and ultimately paid or settled years, or even decades, after the related loss events occur. As a general rule, estimates of accident year or underwriting year ultimate losses for long-tail business are notably more uncertain than those for short and medium-tail business. To date, key actuarial assumptions for long-tail business have been derived extensively from industry benchmarks supplemented with the Company own historical experience. Given the Company's relatively short operating history in comparison to the development tail for this business, the Company does not believe that its own historical loss development for long-tail business has amassed an appropriate volume to serve as a fully credible input into the key actuarial assumptions previously outlined. While industry benchmarks that the Company believes reflect the nature and coverage of its business are considered, actual loss experience may differ from the benchmarks based on industry averages. Due to the length of the development tail for this business, reserve estimates for most accident years and underwriting years are predominantly based on the BF or ELR method and the consideration of qualitative factors.

The Company cannot estimate losses from widespread catastrophic events, such as hurricanes and earthquakes, using the traditional actuarial methods described above. Rather, loss reserves for such events are estimated by management in collaboration with actuaries, claim handlers and underwriters after a catastrophe occurs by completing an in-depth analysis of individual contracts which may potentially be impacted by the catastrophic event. This in-depth analysis may rely on several sources of information, including:

• estimates of the size of insured industry losses from the catastrophic event and the Company's corresponding market share;

• a review of portfolio of contracts performed to identify those contracts which may be exposed to the catastrophic event;

• a review of modeled loss estimates based on information previously reported by customers and brokers, including exposure data obtained during the underwriting process;

• discussions of the impact of the event with customers and brokers and

• catastrophe bulletins published by various independent statistical reporting agencies.

A blend of these information sources is generally used to arrive at aggregate estimates of the ultimate losses arising from the catastrophic event. In subsequent reporting periods, changes in paid and incurred losses in relation to each significant catastrophe are reviewed and adjustments are made to estimates of ultimate losses for each event if there are developments that are different from previous expectations. Adjustments are recorded in the period in which they are identified.

The Company's reserving process involves the collaboration of underwriting, claims, actuarial, legal, ceded reinsurance and finance departments, includes various segmental committee meetings and culminates with the approval of a single point best estimate by the Company's Group Reserving Committee, which comprises senior management. In selecting this best estimate, management considers actuarial estimates and applies informed judgment regarding qualitative factors that may not be fully captured in these actuarial estimates. Such factors include, but are not limited to: the timing of the emergence of claims, volume and complexity of claims, social and judicial trends, potential severity of individual claims and the extent of internal historical loss data versus industry information. While these qualitative factors are considered in arriving at the point estimate, no specific provisions for qualitative factors are established.

Reserve for Losses and Loss Expenses

Gross reserve for losses and loss expenses comprise the following:

As of December 31,	2017		2016
Reserve for reported losses and loss expenses	$	5,137,659	$	3,358,514
Reserve for losses incurred but not reported	7,859,894		6,339,313
Reserve for losses and loss expenses	$	12,997,553	$	9,697,827

Reserve Roll-Forward

The following table presents a reconciliation of beginning and ending gross reserve for losses and loss expenses and net reserve for unpaid losses and loss expenses for the years indicated:

Year ended December 31,	2017			2016			2015
Gross reserve for losses and loss expenses, beginning of year	$	9,697,827		$	9,646,285		$	9,596,797
Less reinsurance recoverable on unpaid losses, beginning of year	(2,276,109		)	(2,031,309		)	(1,890,280		)
Net reserve for unpaid losses and loss expenses, beginning of year	7,421,718			7,614,976			7,706,517
Net incurred losses and loss expenses related to:
Current year	3,487,826			2,496,574			2,419,247
Prior years	(200,054		)	(292,377		)	(243,048		)
	3,287,772			2,204,197			2,176,199
Net paid losses and loss expenses related to:
Current year	(703,796		)	(428,153		)	(343,063		)
Prior years	(1,880,882		)	(1,763,696		)	(1,709,659		)
	(2,584,678		)	(2,191,849		)	(2,052,722		)
Foreign exchange and other	1,713,227			(205,606		)	(215,018		)
Net reserve for unpaid losses and loss expenses, end of year	9,838,039			7,421,718			7,614,976
Reinsurance recoverable on unpaid losses, end of year	3,159,514			2,276,109			2,031,309
Gross reserve for losses and loss expenses, end of year	$	12,997,553		$	9,697,827		$	9,646,285

The Company writes business with loss experience generally characterized as low frequency and high severity in nature, which can result in volatility in its financial results. During 2017, 2016 and 2015, respectively, the Company recognized net losses and loss expenses, net of reinstatement premiums, of $835 million, $204 million and $100 million attributable to catastrophe and weather-related events.

The transfer of the insurance business of AXIS Specialty Australia to a reinsurer was approved by the Irish High Court on February 1, 2017 and the Federal Court of Australia of February 10, 2017. Consequently, the insurance policies, assets and liabilities of AXIS Specialty Australia were transferred to the reinsurer with effect from February 13, 2017. This resulted in the reduction of reserves for losses and loss expenses by $223 million and a reduction in reinsurance recoverables on unpaid and paid losses by $223 million.

On April 1, 2017, the Company acquired 100% ownership interest in Aviabel. At December 31, 2017, foreign exchange and other included reserves for losses and loss expenses of $79 million and reinsurance recoverables on unpaid and paid losses of $5 million related to this acquisition.

On October 2, 2017, the Company acquired 100% ownership interest in Novae. At December 31, 2017, foreign exchange and other included reserves for losses and loss expenses of $2,126 million and reinsurance recoverables on unpaid and paid losses of $788 million related to this acquisition.

During April 2016, the Company entered into a quota share and adverse development cover reinsurance agreement, a retroactive contract which was deemed to have met the established criteria for retroactive reinsurance accounting. At December 31, 2016, foreign exchange and other included reinsurance recoverables of $150 million related to this reinsurance agreement.

Prior Year Development

Prior year reserve development arises from changes to loss and loss expense estimates related to loss events that occurred in previous calendar years. Such development is summarized by segment in the following table:

	Insurance		Reinsurance		Total
Year ended December 31, 2017	$	48,969	$	151,085	$	200,054
Year ended December 31, 2016	55,905		236,472		292,377
Year ended December 31, 2015	23,447		219,601		243,048

Short-tail business

Short-tail business includes the underlying exposures in property and other, marine and aviation reserve classes within the insurance segment and the property and other reserve class within the reinsurance segment.

Development from these classes contributed $60 million, $148 million and $152 million total net favorable prior year reserve development in 2017, 2016 and 2015, respectively, and primarily reflected the recognition of better than expected loss emergence in the years.

Medium-tail business

Medium-tail business consists primarily of insurance and reinsurance professional reserve classes, credit and political risk insurance reserve class, and credit and surety reinsurance reserve class.

The reinsurance professional reserve class recognized $44 million, $30 million and $38 million of net favorable prior year development in 2017, 2016 and 2015, respectively. The net favorable prior year loss developments on this reserve class continued to reflect the generally favorable experience on earlier accident years as the Company continued to transition to more experience based methods. As loss experience on these accident years has generally been better than expected, this resulted in the recognition of net favorable prior year reserve development.

The insurance professional reserve class recorded net favorable prior year development of $26 million in 2017 reflecting the generally favorable experience on earlier accident years as the Company transitions to more experienced based methods. As loss experience has generally been better than expected, this resulted in the recognition of net favorable prior year reserve development. The insurance professional reserve class recorded net favorable prior year reserve development of $14 million in 2016, also driven by overall better than expected development. The insurance professional reserve class recorded adverse prior year development of $14 million in 2015 due to reserve strengthening on the Australian book of business during the three months ended September 30, 2015.

The reinsurance credit and surety reserve class recorded net favorable prior year reserve development of $33 million, $10 million, and $27 million in 2017, 2016, and 2015, respectively due to the recognition of generally better than expected loss emergence.

The credit and political risk reserve class recorded net adverse development of $15 million in 2015 primarily related to an increase in loss estimates for one specific claim.

Long-tail business

Long-tail business consists primarily of liability and motor reserve classes.

The motor reserve class contributed net favorable prior year reserve development of $1 million, $55 million and $37 million, in 2017, 2016 and 2015, respectively. The net favorable prior year reserve development on the motor reserve class in 2016 and 2015 related to favorable loss emergence trends on several classes of business spanning multiple accident years. Net favorable prior year development in 2017 was impacted by the U.K. Ministry of Justice's announcement of a decrease in the discount rate used to calculate lump sum awards in U.K. bodily injury cases, known as the Ogden Rate. Effective March 20, 2017, the Ogden rate changed from plus 2.5% to minus 0.75%.

The reinsurance liability reserve classes contributed net favorable prior year development of $43 million, $44 million and $46 million in 2017, 2016 and 2015, respectively. The net favorable prior year development primarily reflected the progressively increased weight given by management to the generally favorable emerging loss experience on earlier accident years.

This favorable prior year development was partially offset by net adverse prior year development in the insurance liability reserve class of $8 million, $8 million and $27 million in 2017, 2016 and 2015, respectively, primarily related to reserve strengthening within the excess casualty book. In particular, the adverse development during 2015 was mainly driven by a higher frequency of large auto liability claims.

At December 31, 2017 net reserve for losses and loss expenses includes estimated amounts for numerous catastrophe events. The magnitude and/or complexity of losses arising from certain of these events, in particular Hurricanes Harvey, Irma and Maria, the two earthquakes in Mexico and the wildfires in Northern and Southern California in 2017, inherently increases the level of uncertainty and, therefore, the level of management judgment involved in arriving at estimated net reserves for losses and loss expenses. As a result, actual losses for these events may ultimately differ materially from current estimates.

Net Incurred and Paid Claims Development Tables By Accident Year

The following tables present net incurred and paid claims development by accident year, total incurred-but-not-reported liabilities plus expected development on reported claims, cumulative reported claims frequency and claims duration for each reserve class. The development triangles are presented on an accident year basis for both the insurance and reinsurance segments. The Company does not discount unpaid losses and loss expense reserves.

Non-U.S. dollar denominated loss data is converted to U.S. dollar at the rates of exchange in effect at the balance sheet date for material underlying currencies. Fluctuations in currency exchange rates may cause material shifts in loss development. Reserves for losses and loss expenses, disclosed in the Consolidated Balance Sheets, are also revalued using the exchange rate at the balance sheet date.

The Company has presented separate loss development tables for the Aviabel and Novae business prospectively from the date of acquisition. The prospective treatment for the acquisition of Aviabel and Novae was adopted primarily due to the data necessary to produce the loss development tables by accident year not being available prior to the acquisition date. With regard to establishing the fair value of reserves for losses and loss expenses for Novae at the acquisition date, weight was given to the observable value of these reserves based on a Reinsurance to Close (“RITC”) transaction of the Syndicate’s 2015 and prior years of account, which was completed prior to the allocation of purchase price. Management made no change to the initial estimate when establishing its best estimate of reserves for losses and loss expenses at December 31, 2017. This is consistent with the Company's general approach of recognizing all or part of the anticipated cost of third party liability commutations if the transaction has either completed or is considered sufficiently likely to be completed in the near term. 

To the extent that the Company enters into a disposition, the effects of the disposition are reported on a retrospective basis by removing the balances associated with the disposed of business.

There are many considerations in establishing loss reserves and an attempt to evaluate loss reserves using solely the data presented in these tables could be misleading. The Company cautions against mechanical application of standard actuarial methodologies to project ultimate losses using data presented in this disclosure.

Insurance Segment

The reporting of cumulative claims frequency for the reserve classes within the insurance segment has been measured by counting the number of unique claim references including claim references assigned to nil and nominal case reserves. Claim references are grouped by claimant by loss event for each class of business. For certain insurance facilities and business produced by managing general agents where underlying data is reported to the Company in an aggregated format, the information necessary to provide cumulative claims frequency is not available therefore reporting of claims frequency is deemed to be impracticable.

Insurance Property and Other

This reserve class includes property, terrorism as well as accident and health.

The property line of business provides physical loss or damage, business interruption and machinery breakdown cover for virtually all types of property, including commercial buildings, residential premises, construction projects and onshore energy installations. This line of business includes both primary and excess risks, some of which are catastrophe-exposed.

The terrorism line of business provides cover for physical damage and business interruption of an insured following an act of terrorism and includes kidnap & ransom, and crisis management insurance.

The accident and health line of business includes accidental death, travel insurance and specialty health products for employer and affinity groups, as well as accident and health reinsurance for catastrophic or per life events on a quota share and/or excess of loss basis, with aggregate and/or per person deductibles. The accident and health line of business has contributed an increasing portion of the premium earned within this reserve class since 2010 with a large increase in reported claims observed from 2012. In particular, an increase in limited benefits medical business written in 2017 has resulted in a significant increase in reported claims observed in that year.

In general, reporting and payment patterns are relatively short-tailed although they can be volatile due to the incidence of catastrophe events.

Insurance Property and Other
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	312,164	$	260,206	$	251,722	$	242,139	$	226,472	$	225,007	$	220,616	$	218,851	$	217,846	$	216,806	$	982	1,573
2009			117,662		99,367		89,993		82,683		80,718		78,501		78,720		78,368		78,623		971		1,483
2010					175,554		155,343		147,881		122,472		116,888		116,020		115,740		115,289		687		2,310
2011							380,921		356,524		333,911		313,281		310,404		309,197		309,638		2,836		3,737
2012									461,790		472,088		448,763		428,524		424,475		418,869		9,739		27,701
2013											419,392		414,394		387,093		381,550		380,800		6,117		51,238
2014													463,732		459,996		436,130		417,691		6,539		60,151
2015															373,256		373,071		355,883		12,284		43,790
2016																	523,086		574,267		40,961		66,488
2017																			939,565		333,630		237,332
																	Total		$	3,807,431

Insurance Property and Other
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	76,558	$	150,470	$	172,320	$	184,038	$	211,002	$	213,569	$	215,628	$	215,121	$	215,071	$	214,663
2009			31,379		60,166		68,768		72,622		73,538		74,636		76,865		77,187		77,466
2010					48,624		87,059		95,747		106,593		110,785		110,934		110,709		110,763
2011							87,525		217,578		277,260		299,567		298,766		298,559		299,248
2012									107,358		278,870		343,503		366,854		374,485		379,696
2013											129,157		304,207		347,531		361,209		372,338
2014													169,961		341,023		393,868		401,482
2015															123,126		281,377		317,850
2016																	174,455		442,007
2017																			314,839
Total																			2,930,352
All outstanding liabilities before 2008, net of reinsurance																			3,875
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	880,954

Insurance Property and Other
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
34.4%	40.6%	12.2%	5.4%	3.6%	0.8%	0.9%	0.1%	0.2%	(0.2)%

Insurance Marine

This reserve class includes the marine line of business which provides cover for traditional marine classes, including offshore energy, cargo, liability, recreational marine, fine art, specie as well as hull and war. Offshore energy includes physical damage, business interruption, operators extra expense and liability coverage for all aspects of offshore upstream energy, from exploration and construction through the operation and distribution phases. The complex nature of claims arising under marine policies tends to result in reporting and payment patterns that are longer than those of the property and other class. Exposure to natural perils such as windstorm and earthquake can result in volatility.

Insurance Marine
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	99,618	$	106,731	$	101,872	$	100,793	$	93,587	$	87,201	$	83,432	$	83,051	$	82,789	$	82,848	$	381	516
2009			80,665		74,298		69,932		64,601		57,213		55,027		53,622		52,523		52,428		528		477
2010					68,603		70,685		66,639		53,574		51,663		48,823		47,397		45,785		735		472
2011							90,659		78,611		72,463		65,697		65,707		65,919		68,008		1,549		603
2012									89,703		82,729		68,842		70,942		71,917		74,541		12,824		700
2013											80,034		101,276		96,722		97,777		83,064		4,121		733
2014													59,665		44,562		48,471		44,439		7,167		799
2015															158,697		139,931		136,608		16,023		915
2016																	86,324		78,864		19,460		1,372
2017																			74,639		48,739		1,772
																	Total		$	741,224

Insurance Marine
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	14,357	$	52,697	$	69,114	$	77,203	$	78,313	$	82,043	$	82,128	$	82,259	$	82,339	$	82,344
2009			17,431		30,364		39,699		43,243		45,286		45,896		48,430		48,712		49,060
2010					18,062		28,771		33,392		42,554		45,373		46,150		47,088		43,587
2011							26,417		44,168		54,874		57,972		59,816		60,523		64,750
2012									10,730		38,560		44,858		49,631		50,448		52,833
2013											19,313		44,437		55,414		63,637		66,326
2014													6,363		15,277		26,831		26,977
2015															21,467		54,845		108,071
2016																	12,497		32,038
2017																			10,061
Total																			536,047
All outstanding liabilities before 2008, net of reinsurance																			8,213
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	213,390

Insurance Marine
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
22.6%	28.6%	18.8%	8.3%	3.1%	2.3%	3.3%	(2.3)%	0.4%	—%

Insurance Aviation

This reserve class includes the aviation line of business which provides cover for hull and liability, and specific war covers primarily for passenger airlines but also for cargo operations, general aviation operations, airports, aviation authorities, security firms and product manufacturers. The claims reporting pattern varies by insurance coverage provided. Losses arising from war or terrorism and damage to hulls of aircraft are generally reported quickly compared with liability claims which involve passengers and third parties which generally exhibit longer reporting and payment patterns. To date, the claims reported to the Company have predominantly related to damage to hulls, therefore reporting and payment patterns have typically exhibited a relatively short tail.

Insurance Aviation
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	14,485	$	12,021	$	8,516	$	8,354	$	8,256	$	7,108	$	5,937	$	5,851	$	5,996	$	5,905	$	42	187
2009			17,505		14,608		18,800		18,146		16,974		16,674		15,494		14,661		14,388		68		317
2010					12,939		11,729		11,460		9,791		8,807		8,739		8,784		8,574		131		521
2011							17,725		15,400		12,791		9,568		8,437		7,290		7,257		218		734
2012									12,788		10,681		10,807		8,724		7,775		7,730		320		874
2013											15,656		16,344		15,221		15,264		15,579		542		1,027
2014													20,437		23,046		24,368		21,859		982		1,324
2015															29,772		28,512		29,965		2,646		1,917
2016																	29,178		33,641		5,145		1,692
2017																			24,752		12,737		1,177
																	Total		$	169,650

Insurance Aviation
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	488	$	2,063	$	3,084	$	3,666	$	4,216	$	4,487	$	4,663	$	5,269	$	5,526	$	5,519
2009			2,118		3,628		7,071		12,834		13,957		14,322		14,258		13,755		13,547
2010					1,053		4,156		6,341		6,920		7,586		7,708		8,152		8,247
2011							639		2,830		4,521		5,040		5,576		5,826		6,056
2012									957		2,868		4,159		5,958		6,836		7,070
2013											4,402		7,336		9,757		11,462		13,551
2014													3,989		8,033		11,706		13,914
2015															8,090		16,177		21,095
2016																	10,421		19,403
2017																			6,459
Total																			114,861
All outstanding liabilities before 2008, net of reinsurance																			1,611
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	56,400

Insurance Aviation
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
18.7%	24.4%	19.4%	15.5%	9.5%	3.0%	2.8%	2.6%	1.5%	(0.1)%

Insurance Credit and Political Risk

This reserve class includes the credit and political risk line of business which provides credit and political risk insurance products for banks, commodity traders, corporations and multilateral and export credit agencies. Cover is provided for a range of risks including sovereign default, credit default, political violence, currency inconvertibility and non-transfer, expropriation, aircraft non-repossession and contract frustration due to political events.

The credit insurance coverage is primarily for lenders seeking to mitigate the risk of non-payment from their borrowers. In order to claim compensation under a credit insurance contract, the insured (most often a bank) cannot assign, without the Company's prior agreement, the insured contract (most often a loan) to any third party and is normally obliged to hold a material portion of insured asset on their own books, unhedged and uninsured. Claims for this business tend to be characterized by their severity risk, as opposed to their frequency risk. Claim reporting and payment patterns are anticipated to be volatile. Under the notification provisions of credit insurance policies issued by the Company, it anticipates being advised of an insured event within a relatively short time period. As a result, the Company generally estimates ultimate losses based on a contract-by-contract analysis which considers the contracts’ terms, the facts and circumstances of underlying loss events and qualitative input from claims managers.

Insurance Credit and Political Risk
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	52,993	$	63,552	$	48,715	$	45,554	$	45,551	$	45,551	$	45,600	$	45,200	$	44,410	$	44,408	$	—	9
2009			248,084		305,292		326,037		335,558		335,435		335,295		335,315		339,595		339,558		2,040		24
2010					62,415		63,179		63,259		65,598		64,981		65,015		72,105		90,885		13,200		6
2011							58,154		48,665		47,706		48,361		48,333		45,036		33,604		5,973		4
2012									32,602		15,672		12,435		12,447		10,322		47		5		4
2013											26,439		25,684		9,759		9,880		14,941		6,662		1
2014													38,825		70,713		67,109		68,321		10,466		6
2015															30,329		30,368		27,513		4,215		2
2016																	47,250		43,983		20,194		1
2017																			21,237		17,958		2
																	Total		$	684,497

Insurance Credit and Political Risk
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	—	$	69,217	$	45,625	$	45,638	$	45,379	$	45,379	$	44,410	$	44,410	$	44,410	$	44,161
2009			92,844		344,658		346,267		346,243		341,600		345,545		345,545		345,592		340,809
2010					50,000		85,418		90,729		106,769		101,790		101,952		102,158		102,200
2011							32,788		37,205		27,636		27,636		27,636		27,636		27,631
2012									—		—		—		—		40		42
2013											745		2,235		3,726		5,216		11,768
2014													1,924		39,952		61,108		57,855
2015															—		23,309		23,298
2016																	—		23,789
2017																			—
Total																			631,553
All outstanding liabilities before 2008, net of reinsurance																			(1,475		)
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	51,469

Insurance Credit and Political Risk
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
18.8%	54.1%	(4.3)%	3.3%	20.3%	1.1%	(0.5)%	—%	(0.7)%	(0.6)%

Insurance Professional Lines

This reserve class includes the professional line of business which provides directors’ and officers’ liability, errors and omissions liability, employment practices liability, fiduciary liability, crime, professional indemnity, cyber and privacy insurance, medical malpractice and other financial insurance related covers for commercial enterprises, financial institutions and not-for-profit organizations. This business is predominantly written on a claims-made basis. Typically this reserve class is anticipated to exhibit medium to long tail claim reporting and payment patterns.

With respect to key actuarial assumptions, the Company is progressively giving more weight to its own experience when establishing expected loss ratios and selected loss development patterns, though it continues to consider industry benchmarks. Loss reporting patterns for professional lines business tend to be volatile, causing instability in actuarial indications based on incurred loss data until an accident year matures for a number of years. Consequently, initial loss reserves for an accident year are generally based upon an ELR method and the consideration of relevant qualitative factors. As accident years mature, the Company increasingly gives more weight to methods that reflect its actual experience until its selections are based almost exclusively on experience-based methods. The Company evaluates the appropriateness of the transition to experience-based methods at the reserve class level, commencing this transition when it believes that its incurred loss development is sufficient to produce meaningful actuarial indications. The rate at which the Company transitions fully to sole reliance on experience-based methods can vary, depending on its assessment of the stability and relevance of such indications. For some professional lines in the insurance segment, the Company also relies upon the evaluation of the open claim inventory in addition to the commonly employed actuarial methods when establishing reserves.

Insurance Professional Lines
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	238,550	$	278,691	$	280,842	$	298,905	$	296,499	$	309,642	$	329,458	$	327,240	$	326,192	$	325,573	$	9,175	4,558
2009			240,818		244,150		244,751		245,319		256,295		238,902		239,428		215,732		223,737		13,584		5,882
2010					231,232		236,578		234,334		205,801		182,713		158,946		181,232		168,632		26,396		5,669
2011							313,858		315,654		333,321		326,255		330,562		343,782		352,406		50,239		7,211
2012									329,769		375,557		377,277		376,604		364,423		366,725		70,219		8,279
2013											384,755		397,852		398,578		365,818		355,777		95,220		9,371
2014													411,690		412,288		423,087		394,470		157,747		9,650
2015															377,652		377,725		383,959		186,383		9,862
2016																	349,268		352,414		220,770		10,728
2017																			346,582		302,135		9,984
																	Total		$	3,270,275

Insurance Professional Lines
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	4,068	$	22,325	$	68,197	$	124,681	$	167,828	$	189,339	$	214,481	$	249,321	$	267,611	$	268,487
2009			1,689		20,670		44,312		69,050		97,061		107,421		127,033		167,129		179,770
2010					7,857		27,880		53,738		72,840		89,051		99,554		110,156		115,204
2011							6,782		32,351		74,224		108,470		165,755		238,523		283,718
2012									7,824		41,545		100,526		185,059		231,963		255,140
2013											17,739		73,334		130,342		176,899		214,534
2014													23,665		71,510		131,610		194,294
2015															20,403		68,400		138,967
2016																	16,010		71,619
2017																			19,524
Total																			1,741,257
All outstanding liabilities before 2008, net of reinsurance																			30,546
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	1,559,564

Insurance Professional Lines
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
3.7%	10.9%	14.7%	14.5%	12.5%	8.9%	8.9%	10.5%	5.6%	0.3%

Insurance Liability

This reserve class includes the liability line of business which primarily targets primary and low/mid-level excess and umbrella commercial liability risks in the U.S. wholesale markets in addition to primary and excess of loss employers, public, and products liability predominately in the U.K. Target industry sectors include construction, manufacturing, transportation and trucking and other services. The delay between the writing of a contract, notification and subsequent settlement of a claim in respect of that contract results in claim reporting and payment patterns that are typically long tail in nature. A consequence of the claim development tail is that this line of business is particularly exposed, amongst a number of uncertainties, to the potential for unanticipated levels of claim inflation relative to that assumed when the contracts were written. Factors influencing claim inflation on this class can include, but are not limited to, underlying economic and medical inflation, judicial inflation, mass tort and changing social trends.

Insurance Liability
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	82,969	$	79,836	$	80,947	$	81,785	$	82,225	$	81,949	$	101,589	$	102,444	$	108,189	$	94,165	$	11,783	3,790
2009			61,469		64,017		67,410		67,869		76,431		83,282		101,180		98,384		98,999		10,895		2,777
2010					79,401		94,231		98,648		98,134		99,596		98,086		105,145		104,296		12,681		2,206
2011							72,584		75,329		83,118		87,060		85,243		83,731		82,128		19,227		1,788
2012									70,877		70,645		73,282		70,770		68,181		75,342		27,824		1,240
2013											92,153		94,182		94,258		87,502		93,221		24,296		1,562
2014													106,166		122,686		128,568		130,035		41,151		2,440
2015															127,321		126,047		136,615		61,944		3,317
2016																	123,259		129,225		90,482		3,811
2017																			141,644		129,373		2,519
																	Total		$	1,085,670

Insurance Liability
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	1,906	$	8,796	$	18,507	$	27,861	$	37,408	$	47,447	$	51,776	$	55,314	$	61,618	$	87,159
2009			726		4,646		13,305		26,754		31,865		41,323		44,105		83,991		84,427
2010					1,029		15,986		30,809		53,604		61,055		66,140		71,814		86,471
2011							2,761		10,540		20,190		38,377		46,074		54,996		60,263
2012									1,631		5,515		15,412		30,146		37,140		42,745
2013											2,363		23,285		33,324		42,055		60,021
2014													1,419		18,662		49,858		71,630
2015															5,439		22,474		39,767
2016																	6,332		23,335
2017																			4,243
Total																			560,061
All outstanding liabilities before 2008, net of reinsurance																			44,150
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	569,759

Insurance Liability
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
2.5%	11.3%	13.2%	16.2%	10.1%	8.7%	4.8%	19.4%	3.6%	27.1%

Reinsurance Segment

The presentation of net incurred and paid claims development tables by accident year for the reinsurance segment is challenging due to need to the allocate loss information related to proportional treaties to the appropriate accident years. Information related to proportional treaty reinsurance contracts are generally submitted to the Company using quarterly bordereau reporting by underwriting year, with a supplemental listing of large losses. The large losses can be allocated to the corresponding accident years accurately. However, the remaining losses can generally only be allocated to accident years based on estimated premiums earned and loss reporting patterns. To the extent management’s assumptions and allocation procedures differ from the actual loss development patterns, the actual loss development may differ materially from the net incurred and paid claims development presented in the tables below.

The reporting of cumulative claims frequency for the reserve classes within the reinsurance segment is deemed to be impracticable. The information necessary to provide cumulative claims frequency for these reserve classes is not available to the Company.

Reinsurance Property and Other

This reserve class includes property, catastrophe, engineering, agriculture, as well as marine and other.

The catastrophe line of business provides protection for most catastrophic losses that are covered in the underlying policies written by the Company's cedants. The exposure in the underlying policies is principally property exposure but also covers other exposures including workers compensation, personal accident and life. The principal perils in this portfolio are hurricane and windstorm, earthquake, flood, tornado, hail and fire. In some instances, terrorism may be a covered peril or the only peril. The Company underwrites catastrophe reinsurance business principally on an excess of loss basis.

The property line of business provides protection for property damage and related losses resulting from natural and man-made perils contained in underlying personal and commercial policies. While the predominant exposure is to property damage, other risks, including business interruption and other non-property losses, may also be covered when arising from a covered peril. While the most significant exposures typically relate to losses from windstorms, tornadoes and earthquakes, the Company is also exposed to other perils such as freezes, riots, floods, industrial explosions, fires, hail and a number of other loss events. The Company underwrites property reinsurance business on both a proportional and excess of loss basis.

The agriculture line of business provides protection for risks associated with the production of food and fiber on a global basis for primary insurance companies writing multi-peril crop insurance, crop hail, and named peril covers, as well as custom risk transfer mechanisms for agricultural dependent industries with exposures to crop yield and/or price deviations. The Company underwrites agriculture reinsurance business on both a proportional and aggregate stop loss basis.

The engineering line of business provides protection for all types of construction risks and risks associated with erection, testing and commissioning of machinery and plants during the construction stage. This line of business also includes coverage for losses arising from operational failures of machinery, plant and equipment and electronic equipment as well as business interruption.

The marine and other line of business includes marine, aviation and personal accident reinsurance.

In general, reporting and payment patterns are relatively short-tailed and can be volatile due to the incidence of catastrophe events such as hurricanes and earthquakes.

Reinsurance Property and Other
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	677,556	$	577,309	$	593,015	$	571,142	$	557,060	$	546,034	$	529,918	$	524,422	$	523,154	$	523,591	$	(224	)
2009			344,543		288,510		250,630		237,339		230,351		209,335		203,261		205,145		202,300		1,018
2010					619,241		610,563		580,601		594,238		597,427		591,331		583,563		581,616		4,587
2011							1,092,977		1,105,962		1,105,415		1,064,864		1,047,944		1,022,452		1,020,771		8,207
2012									488,776		456,173		445,932		415,327		399,193		394,332		6,544
2013											475,162		452,433		422,160		403,217		397,673		4,083
2014													441,147		461,961		448,887		438,815		45,519
2015															386,614		368,320		369,734		27,033
2016																	452,342		452,169		96,090
2017																			870,456		488,104
																	Total		$	5,251,457

Reinsurance Property and Other
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	158,206	$	316,280	$	444,047	$	497,078	$	510,305	$	514,696	$	514,765	$	519,711	$	519,391	$	517,657
2009			57,796		132,309		164,047		182,556		193,309		192,746		195,614		197,310		193,973
2010					119,385		318,198		412,731		444,822		491,817		521,377		546,253		551,588
2011							242,494		561,377		769,142		872,086		902,188		976,120		991,307
2012									93,847		231,961		305,020		327,361		341,925		351,558
2013											55,047		223,666		336,940		365,089		374,944
2014													65,848		274,886		351,496		369,000
2015															48,116		190,057		282,967
2016																	78,916		231,682
2017																			172,937
Total																			4,037,613
All outstanding liabilities before 2008, net of reinsurance																			6,225
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	1,220,069

Reinsurance Property and Other
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
20.6%	36.6%	20.8%	7.4%	4.2%	3.0%	1.8%	0.9%	(0.9)%	(0.3)%

Reinsurance Credit and Surety

This reserve class includes the credit and surety line of business which provides reinsurance of trade credit insurance products and includes both proportional and excess of loss structures. The underlying insurance indemnifies sellers of goods and services in the event of a payment default by the buyer of those goods and services. The Company provides credit insurance cover to mortgage guaranty insurers and government sponsored entities. Coverages for losses arising from a broad array of surety bonds issued by insurers to satisfy regulatory demands or contract obligations in a variety of jurisdictions around the world are also offered.

Initial and most recent underwriting year loss projections are generally based on the ELR method, with consideration given to qualitative factors. Given that there is a quicker and more stable reporting pattern for trade credit business, the Company generally commences the transition to experience-based methods sooner for trade credit business than for the surety business.

Reinsurance Credit and Surety
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	87,400	$	116,362	$	107,787	$	105,765	$	106,950	$	105,698	$	101,903	$	100,674	$	100,277	$	98,714	$	1,231
2009			147,192		125,656		109,211		108,442		108,149		102,079		98,845		98,469		96,783		1,874
2010					121,893		103,332		96,821		93,648		89,657		82,003		80,680		78,645		5,222
2011							124,030		112,031		110,294		117,586		115,523		106,804		104,997		7,464
2012									163,535		152,873		155,634		152,678		144,084		135,845		11,848
2013											168,361		157,311		148,080		144,095		139,679		17,857
2014													138,056		139,449		146,647		142,909		27,627
2015															163,467		170,980		165,822		36,473
2016																	144,583		144,741		50,815
2017																			135,562		74,667
																	Total		$	1,243,697

Reinsurance Credit and Surety
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	20,891	$	70,349	$	71,501	$	86,796	$	88,604	$	91,014	$	93,282	$	94,040	$	94,446	$	94,601
2009			32,888		78,254		80,744		83,138		87,079		89,736		89,921		89,894		89,986
2010					28,387		50,148		61,983		62,586		64,455		65,722		67,252		68,294
2011							22,640		56,106		74,037		82,015		86,653		88,944		91,307
2012									50,516		88,092		102,976		108,858		112,423		114,251
2013											32,708		78,976		94,347		101,104		108,839
2014													35,839		62,900		88,668		97,957
2015															33,064		84,077		103,123
2016																	42,348		75,170
2017																			34,758
Total																			878,286
All outstanding liabilities before 2008, net of reinsurance																			10,351
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	375,762

Reinsurance Credit and Surety
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
27.3%	32.2%	10.9%	6.0%	3.5%	2.0%	1.7%	0.7%	0.3%	0.2%

Reinsurance Professional Lines

This reserve class includes the professional line of business which provides cover for directors' and officers' liability, employment practices liability, medical malpractice, professional indemnity, environmental liability and miscellaneous errors and omissions insurance risks. The underlying business is predominantly written on a claims-made basis. Business is written on both a proportional and excess of loss basis. Typically, this reserve class is anticipated to exhibit medium to long-tail claim reporting and payment patterns.

With respect to key actuarial assumptions, the Company is progressively giving more weight to its own experience when establishing expected loss ratios and selected loss development patterns, though it continues to consider industry benchmarks. Loss reporting patterns for professional lines business tend to be volatile, causing instability in actuarial indications based on incurred loss data until an accident year matures for a number of years. Consequently, initial loss reserves for an accident year or underwriting year are generally based upon an ELR method and the consideration of relevant qualitative factors. As accident and underwriting years mature, the Company increasingly gives more weight to methods that reflect its actual experience until its selections are based almost exclusively on experience-based methods. The Company evaluates the appropriateness of the transition to experience-based methods at the reserve class level, commencing this transition when it believes that its incurred loss development is sufficient to produce meaningful actuarial indications. The rate at which the Company transitions fully to sole reliance on experience-based methods can vary, depending on its assessment of the stability and relevance of such indications.

Reinsurance Professional Lines
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	176,166	$	183,064	$	182,587	$	178,530	$	176,767	$	173,316	$	174,286	$	173,217	$	172,937	$	169,515	$	6,938
2009			212,285		212,046		216,737		219,447		210,084		209,625		194,753		190,811		181,665		11,657
2010					211,273		211,397		212,359		215,298		215,043		197,548		189,880		180,219		24,929
2011							202,504		202,676		203,706		212,439		209,837		208,973		201,077		51,009
2012									210,612		217,184		222,600		224,737		223,492		213,601		75,647
2013											210,196		215,425		216,528		214,855		214,477		101,607
2014													219,927		219,966		219,960		219,968		85,643
2015															212,536		212,852		215,178		124,029
2016																	195,527		196,852		140,194
2017																			155,882		144,098
																	Total		$	1,948,434

Reinsurance Professional Lines
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	373	$	6,465	$	21,736	$	49,393	$	70,815	$	92,320	$	109,093	$	124,658	$	133,596	$	139,917
2009			914		8,589		32,327		63,180		83,946		108,787		128,608		138,823		143,634
2010					1,759		12,037		31,269		52,187		76,931		107,534		124,158		130,837
2011							1,506		11,829		30,326		57,402		85,052		103,309		120,076
2012									780		10,441		29,730		53,801		86,211		107,581
2013											1,068		12,121		30,666		65,195		81,940
2014													2,020		13,085		48,930		74,748
2015															3,134		13,507		41,610
2016																	1,782		20,624
2017																			2,815
Total																			863,782
All outstanding liabilities before 2008, net of reinsurance																			34,882
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	1,119,534

Reinsurance Professional Lines
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
0.8%	5.3%	11.1%	13.9%	12.4%	12.5%	9.6%	6.2%	4.0%	3.7%

Reinsurance Motor

This reserve class includes the motor line of business which provides cover to insurers for motor liability and motor property damage losses arising from any one occurrence. A loss occurrence can involve one or many claimants where the ceding insurer aggregates the claims from the occurrence.

The Company offers traditional proportional and non-proportional reinsurance as well as structured solutions predominantly relating to European exposures. The business written on a proportional basis has expanded significantly since 2010 and now represents the majority of the premium written within this line of business. Most of the premium relates to a relatively small number of large United Kingdom ("U.K.") and, to a lesser extent, Greek quota share treaties. The motor proportional class generally has a significantly shorter reported and payment pattern relative to the motor non-proportional class.

The motor non-proportional business consists of standard excess of loss contracts written for cedants in several European countries with most of the premium related to two major markets, U.K. and France. Since 2009/2010, an increasing number of large bodily injury settlements in the U.K. market were settled using indexed annuities (Periodical Payment Orders "PPOs"). This led to a materially longer development tail on the older accident years for the U.K. non-proportional motor book. This also resulted in a move towards generally lower treaty attachment points and the inclusion of capitalization clauses on a number of U.K. motor treaties to help mitigate the lengthening of the development tail on more recent accident years. Despite the trend toward a greater number of claims settlements using PPOs, there has been a trend towards generally quicker and more adequate reporting of losses in recent years.

Reinsurance Motor
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	74,058	$	78,924	$	78,193	$	80,897	$	77,937	$	77,027	$	72,330	$	65,983	$	61,702	$	62,557	$	20,916
2009			85,779		83,784		91,915		93,917		96,069		97,089		87,995		82,093		84,458		21,053
2010					103,990		112,528		113,304		112,285		106,058		100,707		90,839		87,253		24,419
2011							160,444		164,579		168,734		175,021		171,007		161,958		150,818		33,732
2012									186,033		176,870		164,734		156,957		151,820		141,923		25,982
2013											169,876		168,554		156,692		146,799		143,186		26,041
2014													190,363		193,691		188,725		185,570		24,003
2015															231,614		229,110		233,172		37,198
2016																	255,354		276,126		55,173
2017																			348,068		170,065
																	Total		$	1,713,131

Reinsurance Motor
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	3,093	$	6,371	$	6,625	$	7,910	$	9,491	$	12,088	$	14,897	$	15,570	$	17,231	$	17,657
2009			2,819		7,134		8,428		10,020		13,627		20,029		22,446		27,248		30,378
2010					7,406		13,316		19,189		22,873		26,489		30,942		34,342		35,444
2011							21,274		46,277		61,691		72,663		79,729		85,995		90,871
2012									29,727		55,282		70,634		80,891		87,658		91,896
2013											34,607		56,009		70,849		81,419		87,407
2014													44,225		77,736		98,483		107,090
2015															58,884		97,495		118,902
2016																	61,938		109,559
2017																			71,052
Total																			760,256
All outstanding liabilities before 2008, net of reinsurance																			129,548
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	1,082,423

Reinsurance Motor
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
16.8%	13.2%	7.6%	5.0%	4.1%	4.8%	3.6%	2.7%	3.2%	0.7%

Reinsurance Liability

This reserve class includes the liability line of business which provides cover to insurers of standard casualty business, excess and surplus casualty business and specialty casualty programs. The primary focus of the underlying business is general liability, although workers' compensation and auto liability are also covered.

Claim reporting and payment patterns are typically long-tail in nature and, therefore, subject to increased uncertainty surrounding future loss development. In particular, claims can be subject to inflation from a number of sources including, but not limited to, economic and medical inflation, judicial inflation and changing social trends.

Reinsurance Liability
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance																				At December 31, 2017
	For the Years Ended December 31,																				Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	140,069	$	140,460	$	141,152	$	141,553	$	139,564	$	133,917	$	111,873	$	106,942	$	95,649	$	86,008	$	10,016
2009			175,100		176,187		182,970		180,596		188,090		208,301		195,679		181,488		171,979		23,215
2010					173,358		172,261		183,773		184,180		202,649		192,051		182,794		166,533		29,101
2011							174,125		173,815		175,279		193,228		200,190		196,948		196,277		34,097
2012									168,641		164,742		168,956		173,596		174,765		172,124		43,129
2013											173,966		177,606		183,683		185,689		185,321		71,652
2014													201,355		204,323		206,100		202,130		91,483
2015															216,076		216,518		217,480		125,377
2016																	241,952		247,768		171,869
2017																			266,945		226,036
																	Total		$	1,912,565

Reinsurance Liability
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	For the Years Ended December 31,
Accident Year	2008 Unaudited		2009 Unaudited		2010 Unaudited		2011 Unaudited		2012 Unaudited		2013 Unaudited		2014 Unaudited		2015 Unaudited		2016		2017
2008	$	2,160	$	9,952	$	21,953	$	30,028	$	36,567	$	43,509	$	51,922	$	53,882	$	58,022	$	63,903
2009			1,705		17,104		44,552		56,730		73,521		105,410		125,329		129,644		135,031
2010					2,484		17,659		46,207		62,300		83,976		97,617		108,938		119,872
2011							5,191		21,297		40,021		70,283		92,696		112,581		123,719
2012									3,542		12,809		28,418		58,855		78,368		101,343
2013											5,978		22,259		52,360		69,098		88,327
2014													7,117		28,699		48,498		70,389
2015															7,273		27,473		54,646
2016																	11,891		37,819
2017																			12,073
Total																			807,122
All outstanding liabilities before 2008, net of reinsurance																			42,182
Liabilities for claims and claim adjustment expenses, net of reinsurance																			$	1,147,625

Reinsurance Liability
Average annual percentage payout of incurred claims by age, net of reinsurance
Year 1	Year 2	Year 3	Year 4	Year 5	Year 6	Year 7	Year 8	Year 9	Year 10
2.9%	8.9%	13.0%	11.3%	10.6%	11.6%	8.5%	3.8%	4.0%	6.8%

Aviabel Aviation

In April 2017, the Company acquired Aviabel, an insurance and reinsurance operation founded in 1935 with headquarters in Europe. Aviabel’s main lines of business consist of general aviation, airlines, products and manufacturers, airports and treaty reinsurance. With regards to airlines, manufactures and airports, Aviabel focuses on smaller operators rather than the large players. The claims reporting pattern varies by coverage provided but are typically short tailed in nature.

Aviabel
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance							At December 31, 2017
Accident Year	Net claim and allocated claim adjustment expense reserves at the Acquisition Date		Net incurred claims and allocated claim adjustment expenses from the Acquisition Date to December 31, 2017			Total acquired net claim and allocated claim adjustment expense reserves and net incurred claims and allocated claim adjustment expenses from the Acquisition Date to December 31, 2017		Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims		Cumulative Number of Reported Claims
2008	$	998	$	(293	)	$	705	$	30	1,066
2009	842		82			924		25		1,347
2010	1,516		(39		)	1,477		46		1,452
2011	1,418		(423		)	995		43		1,420
2012	5,248		(1,066		)	4,183		177		1,380
2013	5,702		956			6,658		200		1,286
2014	10,589		(1,636		)	8,953		804		1,373
2015	15,004		(1,575		)	13,429		1,650		1,475
2016	19,388		2,134			21,522		4,278		1,535
2017	7,666		27,096			34,762		7,180		1,114
	$	68,371	$	25,237		$	93,608

Aviabel
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	From the Acquisition Date to December 31, 2017
Accident Year
2008		$	(33	)
2009		1
2010		97
2011		20
2012		661
2013		425
2014		1,944
2015		3,291
2016		5,453
2017		14,970
Total		26,830
	All outstanding liabilities before 2008, net of reinsurance	10,626
	Liabilities for claims and claim adjustment expenses, net of reinsurance	$	77,405

Novae

In October 2017, the Company acquired Novae, a diversified property and casualty (re)insurance business operating through Syndicate 2007 at Lloyd’s. Novae writes a wide range of property, marine, aviation, credit and political risk, professional lines, motor and liability business on a worldwide basis. In addition, cover is also offered for various other lines of business, including agriculture reinsurance, bloodstock, construction, accident and health, political violence and engineering reinsurance.

The Company has determined that reporting of cumulative claims frequency for direct insurance lines of business is impracticable as data by accident year is not available. Further for certain insurance facilities and business produced by managing general agents where underlying data is reported to the Company in an aggregated format, the information necessary to provide cumulative claims frequency is not available therefore reporting of claims frequency is deemed to be impracticable. In addition, the information necessary to provide cumulative claims frequency for reinsurance lines of business is not available to the Company, therefore reporting of claims frequency is deemed to be impracticable.

Property: The property line of business includes exposures related to worldwide direct property facilities for retail and small commercial risks, worldwide catastrophe reinsurance written on a proportional and excess of loss basis, and worldwide direct and facultative cover of larger commercial risks. In general, reporting and payment patterns are relatively short-tailed although they can be volatile due to the incidence of catastrophe events.

Marine: The marine line of business covers marine liability, energy, hull, cargo, specie and war exposures and includes risks which are mostly written on a direct basis. In addition, a relatively small amount of marine business is written on an excess of loss basis. The complex nature of claims arising under marine policies tends to result in reporting and payment patterns that are longer than those of the property lines of business.

Aviation: The aviation line of business provides hull, liability, and war cover and predominantly relates to an excess of loss reinsurance account, with a smaller amount of satellite and general aviation business written on a proportional basis. Payments relating to hull damage can settle relatively quickly but an element of the claims profile will often be longer tail due to liability exposures.

Credit & political risk: International trade credit and political risks business was written from 2000 onwards. Typically this business is anticipated to exhibit medium to long tail claim reporting and payment patterns.

Professional Lines: Professional lines business provides cover for directors’ and officers’ liability, errors and omissions liability, crime, professional indemnity, cyber and medical malpractice and includes risks which are mainly written on a direct basis. Most professional lines business written from 2002 onwards relates to non-U.S. exposures. Typically, this business is anticipated to exhibit medium to long tail claim reporting and payment patterns.

Motor: Motor line of business was written on a direct basis until this business was discontinued in 2015. Motor business has been written on an excess of loss basis since 2010. The business predominantly covers U.K. based risks. Typically, this business is anticipated to exhibit long-tail claim reporting and payment patterns.

Liability: The general liability reinsurance line of business provides cover for directors’ and officers’ liability, errors and omissions liability, crime, professional indemnity, cyber and medical malpractice written on an excess of loss basis from 2010 onwards. Most general liability reinsurance business written relates to non-U.S. commercial liability insurance but also includes U.S. casualty excess of loss reinsurance from 2015. Claim reporting and payment patterns are typically long-tail in nature and, therefore, subject to increased uncertainty surrounding future loss development. In particular, claims can be subject to inflation from a number of sources including, but not limited to, economic and medical inflation, judicial inflation and changing social trends.

Novae
	Incurred Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance						At December 31, 2017
Accident Year	Net claim and allocated claim adjustment expense reserves at the Acquisition Date		Net incurred claims and allocated claim adjustment expenses from the Acquisition Date to December 31, 2017		Total acquired net claim and allocated claim adjustment expense reserves and net incurred claims and allocated claim adjustment expenses from the Acquisition Date to December 31, 2017		Total of Incurred-But-Not-Reported Liabilities Plus Expected Development on Reported Claims
2008	$	20,515	$	—	$	20,515	$	3,552
2009	25,486		—		25,486		714
2010	23,308		—		23,308		2,781
2011	59,648		—		59,648		11,204
2012	87,292		—		87,292		8,695
2013	76,786		—		76,786		12,504
2014	123,955		—		123,955		17,024
2015	184,606		—		184,606		36,619
2016	307,014		—		307,014		54,356
2017	293,520		135,493		429,013		222,330
	$	1,202,130	$	135,493	$	1,337,624

Novae
	Cumulative Paid Claims and Allocated Claim Adjustment Expenses, Net of Reinsurance
	From the Acquisition Date to December 31, 2017
Accident Year
2008		$	1,458
2009		1,147
2010		3,197
2011		4,332
2012		7,352
2013		5,878
2014		12,370
2015		19,349
2016		51,065
2017		33,278
Total		139,427
	All outstanding liabilities before 2008, net of reinsurance	102,164
	Liabilities for claims and claim adjustment expenses, net of reinsurance	$	1,300,361

Reconciliation of Development Tables to Consolidated Balance Sheet

The following table reconciles the reserves for loss and loss expenses as of December 31, 2017 as reported in the Consolidated Balance Sheet to the reserves for loss and loss expenses included in the development tables:

Reconciliation of the Disclosure of Incurred and Paid Claims Development to the Liability for Unpaid Claims and Claim Adjustment Expenses
	At December 31, 2017
	Net outstanding liabilities		Reinsurance recoverable on unpaid claims		Gross outstanding liabilities
Insurance Segment
Property and Other	$	880,954	$	181,101	$	1,062,055
Marine	213,390		106,466		319,856
Aviation	56,400		8,945		65,345
Credit and Political Risk	51,469		1,384		52,853
Professional Lines	1,559,564		853,130		2,412,694
Liability	569,759		896,266		1,466,025
Total Insurance Segment	3,331,536		2,047,292		5,378,828
Reinsurance Segment
Property and Other	1,220,069		214,394		1,434,463
Credit and Surety	375,762		13,061		388,823
Professional Lines	1,119,534		37,822		1,157,356
Motor	1,082,423		3,666		1,086,089
Liability	1,147,625		66,692		1,214,317
Total Reinsurance Segment	4,945,413		335,635		5,281,048
Aviabel	77,405		5,329		82,734
Novae	1,300,361		771,258		2,071,619
Total	$	9,654,715	$	3,159,514	12,814,229
Unallocated claims adjustment expenses					170,168
Foreign exchange and other(1)					(45,262		)
Assumed reserves related to retroactive transactions					58,418
Total liability for unpaid claims and claims adjustment expense					$	12,997,553

(1) Non-U.S. dollar denominated loss data is converted to U.S dollar at the rates of exchange in effect at the balance sheetdate for material underlying currencies. Fluctuations in currency exchange rates cause material shifts in loss development. Reserves for losses and loss expenses, disclosed in the Consolidated Balance Sheets, are also revalued using the exchange rate at the balance sheet date.