The determination of the Company’s business segments is based on the manner in which management monitors the performance of its operations. The Company reports one operating segment, Property and Casualty Reinsurance. The Company has also identified a corporate function that includes the Company’s investment income on capital, certain general and administrative expenses related to corporate activities, interest expense, foreign exchange gains (losses) and income tax (expense) benefit. As of December 31, 2015, all investments in the Catastrophe Fund had been redeemed. In February 2016, the Company completed the dissolution of the Catastrophe Fund and Catastrophe Reinsurer. As a result, there is no further activity in the Catastrophe Risk Management segment.

The following is a summary of the Company’s operating segment results for the three and nine months ended September 30, 2016 and 2015:



	Three months ended September 30, 2016
	Property and Casualty Reinsurance			Catastrophe Risk Management		Corporate			Total
Revenues	($ in thousands)
Gross premiums written	$	142,573		$	—	$	—		$	142,573
Gross premiums ceded	(927		)	—		—			(927		)
Net premiums written	141,646			—		—			141,646
Change in net unearned premium reserves	(13,463		)	—		—			(13,463		)
Net premiums earned	128,183			—		—			128,183
Expenses
Loss and loss adjustment expenses incurred, net	85,015			—		—			85,015
Acquisition costs, net	45,127			—		—			45,127
General and administrative expenses	6,380			—		5,974			12,354
Total expenses	136,522			—		5,974			142,496
Net underwriting loss	(8,339		)	n/a		n/a			n/a
Net investment income	22,031			—		66,325			88,356
Other expenses	(347		)	—		—			(347		)
Interest expense	—			—		(2,069		)	(2,069		)
Foreign exchange gains	—			—		3,905			3,905
Income tax expense	—			—		(2,484		)	(2,484		)
Segment income (loss) including non-controlling interests	13,345			—		59,703			73,048
Segment income attributable to non-controlling interests	—			—		(967		)	(967		)
Segment income (loss)	$	13,345		$	—	$	58,736		$	72,081

Property and Casualty Reinsurance - Underwriting Ratios (1):
Loss ratio	66.3		%
Acquisition cost ratio	35.2		%
Composite ratio	101.5		%
General and administrative expense ratio	5.0		%
Combined ratio	106.5		%

(1) Underwriting ratios are calculated by dividing the related expense by net premiums earned.



	Nine months ended September 30, 2016
	Property and Casualty Reinsurance			Catastrophe Risk Management		Corporate			Total
Revenues	($ in thousands)
Gross premiums written	$	536,595		$	—	$	—		$	536,595
Gross premiums ceded	(2,352		)	—		—			(2,352		)
Net premiums written	534,243			—		—			534,243
Change in net unearned premium reserves	(136,136		)	—		—			(136,136		)
Net premiums earned	398,107			—		—			398,107
Expenses
Loss and loss adjustment expenses incurred, net	273,822			—		—			273,822
Acquisition costs, net	145,296			—		—			145,296
General and administrative expenses	19,527			—		14,358			33,885
Total expenses	438,645			—		14,358			453,003
Net underwriting loss	(40,538		)	n/a		n/a			n/a
Net investment income	32,868			—		101,724			134,592
Other expenses	(6,226		)	—		—			(6,226		)
Interest expense	—			—		(6,163		)	(6,163		)
Foreign exchange gains	—			—		14,359			14,359
Income tax expense	—			—		(5,865		)	(5,865		)
Segment income (loss) including non-controlling interests	(13,896		)	—		89,697			75,801
Segment income attributable to non-controlling interests	—			—		(1,473		)	(1,473		)
Segment income (loss)	$	(13,896	)	$	—	$	88,224		$	74,328

Property and Casualty Reinsurance - Underwriting Ratios (1):
Loss ratio	68.8		%
Acquisition cost ratio	36.5		%
Composite ratio	105.3		%
General and administrative expense ratio	4.9		%
Combined ratio	110.2		%


(1)	Underwriting ratios are calculated by dividing the related expense by net premiums earned.



	Three months ended September 30, 2015
	Property and Casualty Reinsurance			Catastrophe Risk Management			Corporate			Total
Revenues	($ in thousands)
Gross premiums written	$	205,729		$	(146	)	$	—		$	205,583
Gross premiums ceded	(375		)	—			—			(375		)
Net premiums written	205,354			(146		)	—			205,208
Change in net unearned premium reserves	3,597			—			—			3,597
Net premiums earned	208,951			(146		)	—			208,805
Expenses
Loss and loss adjustment expenses incurred, net	158,387			150			—			158,537
Acquisition costs, net	50,527			(18		)	—			50,509
General and administrative expenses	5,872			32			3,918			9,822
Total expenses	214,786			164			3,918			218,868
Net underwriting loss	(5,835		)	n/a			n/a			n/a
Net investment income (loss)	(51,988		)	1			(141,169		)	(193,156		)
Other expenses	(670		)	—			—			(670		)
Interest expense	—			—			(2,074		)	(2,074		)
Foreign exchange gains	—			—			746			746
Income tax benefit	—			—			7,781			7,781
Segment income (loss) including non-controlling interests	(58,493		)	(309		)	(138,634		)	(197,436		)
Segment loss attributable to non-controlling interests	—			140			1,581			1,721
Segment income (loss)	$	(58,493	)	$	(169	)	$	(137,053	)	$	(195,715	)

Property and Casualty Reinsurance - Underwriting Ratios (1):
Loss ratio	75.8		%
Acquisition cost ratio	24.2		%
Composite ratio	100.0		%
General and administrative expense ratio	2.8		%
Combined ratio	102.8		%

(1) Underwriting ratios are calculated by dividing the related expense by net premiums earned.



	Nine months ended September 30, 2015
	Property and Casualty Reinsurance			Catastrophe Risk Management			Corporate			Total
Revenues	($ in thousands)
Gross premiums written	$	603,303		$	(44	)	$	—		$	603,259
Gross premiums ceded	(1,852		)	—			—			(1,852		)
Net premiums written	601,451			(44		)	—			601,407
Change in net unearned premium reserves	(133,001		)	52			—			(132,949		)
Net premiums earned	468,450			8			—			468,458
Expenses
Loss and loss adjustment expenses incurred, net	316,186			150			—			316,336
Acquisition costs, net	152,665			(1		)	—			152,664
General and administrative expenses	18,681			463			16,653			35,797
Total expenses	487,532			612			16,653			504,797
Net underwriting loss	(19,082		)	n/a			n/a			n/a
Net investment income (loss)	(23,623		)	69			(66,073		)	(89,627		)
Other expenses	(5,686		)	—			—			(5,686		)
Interest expense	—			—			(5,162		)	(5,162		)
Foreign exchange gains	—			—			800			800
Income tax benefit	—			—			5,768			5,768
Segment loss including non-controlling interests	(48,391		)	(535		)	(81,320		)	(130,246		)
Segment loss attributable to non-controlling interests	—			156			507			663
Segment loss	$	(48,391	)	$	(379	)	$	(80,813	)	$	(129,583	)

Property and Casualty Reinsurance - Underwriting Ratios (1):
Loss ratio	67.5		%
Acquisition cost ratio	32.6		%
Composite ratio	100.1		%
General and administrative expense ratio	4.0		%
Combined ratio	104.1		%


(1)	Underwriting ratios are calculated by dividing the related expense by net premiums earned.

The following table lists the number of contracts that individually contributed more than 10% of total gross premiums written for the three and nine months ended September 30, 2016 and 2015 as a percentage of total gross premiums written in the relevant period:



	Three months ended				Nine months ended
	September 30, 2016		September 30, 2015		September 30, 2016		September 30, 2015
Largest contract	42.4	%	44.5	%	20.9	%	15.5	%
Second largest contract	26.8	%	27.1	%	11.3	%	15.2	%
Third largest contract	10.1	%	11.3	%	n/a		n/a
Total for contracts contributing greater than 10% each	79.3	%	82.9	%	32.2	%	30.7	%
Total for contracts contributing less than 10% each	20.7	%	17.1	%	67.8	%	69.3	%
	100.0	%	100.0	%	100.0	%	100.0	%

The following table provides a breakdown of the Company’s gross premiums written by line of business for the three and nine months ended September 30, 2016 and 2015:



	Three months ended									Nine months ended
	September 30, 2016				September 30, 2015					September 30, 2016				September 30, 2015
	($ in thousands)
Property	$	56,632	39.7	%	$	21,863		10.6	%	$	63,714	11.9	%	$	70,854		11.7	%
Casualty	26,640		18.7	%	161,980			78.9	%	187,146		34.9	%	320,990			53.2	%
Specialty	59,301		41.6	%	21,886			10.6	%	285,735		53.2	%	211,459			35.1	%
Total property and casualty reinsurance	142,573		100.0	%	205,729			100.1	%	536,595		100.0	%	603,303			100.0	%
Catastrophe risk management	—		—	%	(146		)	(0.1	)%	—		—	%	(44		)	—	%
	$	142,573	100.0	%	$	205,583		100.0	%	$	536,595	100.0	%	$	603,259		100.0	%

The following table provides a breakdown of the Company’s gross premiums written by prospective and retroactive reinsurance contracts for the three and nine months ended September 30, 2016 and 2015:



	Three months ended								Nine months ended
	September 30, 2016				September 30, 2015				September 30, 2016				September 30, 2015
	($ in thousands)
Prospective	$	142,573	100.0	%	$	114,029	55.5	%	$	536,595	100.0	%	$	495,195	82.1	%
Retroactive (1)	—		—	%	91,554		44.5	%	—		—	%	108,064		17.9	%
	$	142,573	100.0	%	$	205,583	100.0	%	$	536,595	100.0	%	$	603,259	100.0	%


(1)	Includes all retroactive exposure in reinsurance contracts.

The Company records the gross premium written and earned at the inception of the contract for retroactive exposures in reinsurance contracts.

Substantially all of the Company’s business is sourced through reinsurance brokers. The following table sets forth the Company’s premiums written by source that individually contributed more than 10% of total gross premiums written for the three and nine months ended September 30, 2016 and 2015:



	Three months ended								Nine months ended
	September 30, 2016				September 30, 2015				September 30, 2016				September 30, 2015
	($ in thousands)
Largest broker	$	95,073	66.7	%	$	91,554	44.5	%	$	186,737	34.8	%	$	173,888	28.8	%
Second largest broker	27,461		19.3	%	83,588		40.7	%	180,631		33.7	%	128,512		21.3	%
Third largest broker	n/a		n/a		n/a		n/a		89,756		16.7	%	91,554		15.2	%
Other	20,039		14.0	%	30,441		14.8	%	79,471		14.8	%	209,305		34.7	%
	$	142,573	100.0	%	$	205,583	100.0	%	$	536,595	100.0	%	$	603,259	100.0	%

The following table provides a breakdown of the Company’s gross premiums written by domicile of the ceding companies for the three and nine months ended September 30, 2016 and 2015:



	Three months ended								Nine months ended
	September 30, 2016				September 30, 2015				September 30, 2016				September 30, 2015
	($ in thousands)
United States	$	123,233	86.4	%	$	52,515	25.5	%	$	290,971	54.2	%	$	242,382	40.2	%
Bermuda	18,538		13.0	%	60,239		29.3	%	65,078		12.1	%	104,288		17.3	%
United Kingdom	802		0.6	%	92,829		45.2	%	180,546		33.7	%	256,589		42.5	%
	$	142,573	100.0	%	$	205,583	100.0	%	$	536,595	100.0	%	$	603,259	100.0	%