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Reserve for Loss and Loss Expense (Tables)

12 Months Ended

Dec. 31, 2017

Insurance Loss Reserves [Abstract]

Schedule of Roll Forward of Reserve for Loss and Loss Expense

($ in thousands)		2017				2016			2015
Gross reserves for loss and loss expense, at beginning of year		$	3,691,719			3,517,728			3,477,870
Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of year		611,200				551,019			571,978
Net reserves for loss and loss expense, at beginning of year		3,080,519				2,966,709			2,905,892
Incurred loss and loss expense for claims occurring in the:
Current year		1,384,266				1,300,565			1,217,550
Prior years		(39,192		)		(65,768	)		(69,009	)
Total incurred loss and loss expense		1,345,074				1,234,797			1,148,541
Paid loss and loss expense for claims occurring in the:
Current year		497,486				450,811			446,550
Prior years		742,722				670,176			641,174
Total paid loss and loss expense		1,240,208				1,120,987			1,087,724
Net reserves for loss and loss expense, at end of year		3,185,385				3,080,519			2,966,709
Add: Reinsurance recoverable on unpaid loss and loss expense, at end of year		585,855				611,200			551,019
Gross reserves for loss and loss expense at end of year		$	3,771,240			3,691,719			3,517,728

Schedule of (Favorable)/ Unfavorable Prior Year Development

(Favorable)/Unfavorable Prior Year Development
($ in millions)		2017				2016			2015
General Liability		$	(48.3	)		(45.0	)		(51.0	)
Commercial Automobile		35.6				25.3			2.4
Workers Compensation		(52.3		)		(56.0	)		(37.0	)
Businessowners' Policies		1.9				1.8			2.2
Commercial Property		8.7				0.3			(3.0	)
Homeowners		0.4				1.7			1.5
Personal Automobile		6.7				1.0			0.4
E&S Casualty Lines		10.0				6.0			16.0
Other		(1.9		)		(0.9	)		(0.5	)
Total		$	(39.2	)		(65.8	)		(69.0	)

Schedule of Exposure to Various Asbestos and Environmental Claims

		2017
($ in millions)		Gross				Net
Asbestos		$	7.6			6.3
Landfill sites		12.4				7.7
Underground storage tanks		8.4				7.2
Total		$	28.4			21.2

Schedule of Roll Forward of Gross and Net Asbestos and Environmental Incurred Losses and Loss Expenses and Related Reserves

		2017							2016						2015
($ in thousands)		Gross				Net			Gross			Net			Gross			Net
Asbestos
Reserves for loss and loss expense at beginning of year		$	7,847			6,615			8,024			6,793			8,751			7,314
Incurred loss and loss expense		—				—			77			77			(428	)		(77	)
Less: loss and loss expense paid		(270		)		(269	)		(254	)		(255	)		(299	)		(444	)
Reserves for loss and loss expense at the end of year		$	7,577			6,346			7,847			6,615			8,024			6,793
Environmental
Reserves for loss and loss expense at beginning of year		$	22,115			16,101			22,387			16,368			21,902			15,680
Incurred loss and loss expense		126				—			1,406			1,303			3,396			3,397
Less: loss and loss expense paid		(1,403		)		(1,235	)		(1,678	)		(1,570	)		(2,911	)		(2,709	)
Reserves for loss and loss expense at the end of year		$	20,838			14,866			22,115			16,101			22,387			16,368
Total Asbestos and Environmental Claims
Reserves for loss and loss expense at beginning of year		$	29,962			22,716			30,411			23,161			30,653			22,994
Incurred loss and loss expense		126				—			1,483			1,380			2,968			3,320
Less: loss and loss expense paid		(1,673		)		(1,504	)		(1,932	)		(1,825	)		(3,210	)		(3,153	)
Reserves for loss and loss expense at the end of year		$	28,415			21,212			29,962			22,716			30,411			23,161

Short-duration Insurance Contracts, Claims Development [Table Text Block]

All Lines (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	957,247		988,584		990,931		964,862		947,306		936,975		927,958		931,785		926,017		923,978			41,791		85,338
2009				920,143		941,972		916,691		883,590		870,057		869,927		857,960		853,401		848,413			41,937		85,575
2010						950,114		973,742		977,959		956,600		943,118		922,404		915,131		907,074			50,293		94,258
2011								1,042,576		1,061,667		1,062,233		1,056,107		1,033,518		1,023,726		1,019,351			63,891		104,500
2012										1,065,437		1,071,290		1,020,655		998,028		973,089		973,644			77,542		103,745
2013												1,044,142		1,062,045		1,047,230		1,021,007		1,002,316			116,449		90,755
2014														1,107,513		1,133,798		1,146,990		1,124,014			171,913		94,375
2015																1,114,081		1,130,513		1,144,830			256,758		92,891
2016																		1,188,608		1,203,634			416,010		92,191
2017																				1,270,110			634,863		88,941
																		Total		10,417,364

All Lines (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	286,314		489,633		609,851		690,016		764,196		798,996		819,280		839,392		853,769		860,745
2009				277,275		442,417		540,982		634,902		695,249		736,100		760,589		775,885		784,713
2010						328,826		509,910		625,229		704,895		773,536		803,773		823,770		835,532
2011								391,944		585,867		692,730		782,655		852,202		901,801		924,111
2012										378,067		555,819		651,544		743,742		810,135		856,195
2013												335,956		518,872		644,475		748,758		833,823
2014														405,898		614,075		736,154		855,959
2015																376,641		581,203		725,385
2016																		387,272		617,958
2017																				433,440
																		Total		7,727,861
										All outstanding liabilities before 2008, net of reinsurance										352,192
								Liabilities for loss and loss adjustment expenses, net of reinsurance												3,041,694

General Liability (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	250,239		243,755		243,536		234,770		233,712		224,236		219,551		221,640		221,203		219,617			14,326		13,769
2009				237,913		241,625		233,530		223,146		212,947		211,243		206,387		205,741		201,568			17,629		13,841
2010						215,208		228,680		242,499		237,154		222,328		211,619		208,968		202,394			18,403		12,672
2011								227,769		228,720		239,480		230,785		217,256		211,196		212,011			25,729		11,579
2012										238,979		245,561		215,083		194,144		175,305		175,268			27,702		9,922
2013												250,609		251,421		239,776		225,709		210,785			53,014		10,226
2014														244,312		249,946		257,132		239,333			80,168		10,391
2015																254,720		245,710		246,990			124,639		9,987
2016																		277,214		272,048			178,904		9,617
2017																				293,747			249,085		8,194
																		Total		2,273,761

General Liability (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	16,397		45,595		82,421		113,088		151,055		166,394		176,873		186,896		194,257		198,360
2009				14,346		37,143		64,970		103,213		130,554		151,920		166,767		176,316		180,621
2010						15,726		46,201		80,018		113,050		143,360		161,487		172,394		178,179
2011								13,924		42,692		73,643		102,978		135,377		159,768		170,525
2012										13,030		35,241		56,580		89,008		109,448		130,866
2013												12,789		35,113		72,127		104,587		139,114
2014														14,901		46,825		79,972		121,969
2015																14,665		39,978		78,668
2016																		15,684		46,549
2017																				17,366
																		Total		1,262,217
										All outstanding liabilities before 2008, net of reinsurance										80,514
								Liabilities for loss and loss adjustment expenses, net of reinsurance												1,092,058

Workers Compensation (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	219,616		243,186		255,810		250,423		241,921		245,993		244,100		243,512		238,836		238,218			25,993		14,401
2009				197,504		215,946		213,036		210,109		210,756		216,992		212,536		208,611		208,142			22,575		12,217
2010						198,371		214,469		212,815		211,030		214,916		212,448		208,155		204,423			28,964		12,184
2011								205,238		218,973		214,743		215,114		210,591		205,708		200,674			32,881		11,845
2012										203,864		208,036		199,360		195,197		188,596		187,359			36,233		11,605
2013												199,794		194,318		187,658		173,160		166,662			34,776		11,366
2014														199,346		187,065		182,579		172,515			42,869		10,482
2015																193,729		194,639		183,604			42,287		10,530
2016																		196,774		184,946			70,424		10,509
2017																				195,202			112,086		10,182
																		Total		1,941,745

Workers Compensation (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	39,628		100,678		139,144		158,083		171,403		180,556		188,206		191,265		195,962		198,512
2009				37,885		87,299		117,019		133,116		145,417		154,726		160,529		164,336		167,894
2010						46,795		93,281		122,442		137,184		149,086		153,795		158,078		162,796
2011								42,941		90,836		118,847		134,646		139,232		149,269		154,320
2012										40,911		86,909		108,211		122,755		132,052		139,477
2013												36,829		74,568		96,376		109,739		118,669
2014														35,924		78,944		100,876		113,626
2015																33,857		77,320		98,195
2016																		34,525		78,531
2017																				40,375
																		Total		1,272,395
										All outstanding liabilities before 2008, net of reinsurance										247,121
								Liabilities for loss and loss adjustment expenses, net of reinsurance												916,471

Commercial Automobile (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	196,370		195,823		190,349		187,100		187,417		182,785		180,902		183,736		183,618		183,151			736		24,129
2009				199,541		191,079		182,724		169,858		166,682		162,911		161,251		161,923		161,300			897		24,652
2010						187,562		189,305		187,778		181,923		179,854		172,969		173,157		173,471			1,491		25,301
2011								174,006		183,044		182,325		178,421		172,617		174,882		174,514			2,937		25,272
2012										179,551		191,947		183,527		184,289		184,367		186,128			3,880		23,889
2013												188,289		205,282		209,197		207,994		210,410			8,258		25,392
2014														200,534		212,725		216,824		219,925			19,053		27,338
2015																220,994		240,958		253,074			36,137		28,818
2016																		255,187		274,367			71,303		30,480
2017																				301,274			132,814		30,187
																		Total		2,137,614

Commercial Automobile (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	69,053		104,711		130,857		151,741		166,487		173,795		175,244		180,779		181,779		181,979
2009				63,126		94,406		113,697		137,564		149,949		155,560		158,303		159,723		160,013
2010						68,098		99,254		128,015		146,913		163,513		167,227		169,100		169,793
2011								69,849		99,196		121,576		142,507		157,291		166,082		170,000
2012										73,316		105,371		127,235		148,669		168,114		176,656
2013												76,469		109,893		140,015		169,850		189,626
2014														80,810		117,169		148,884		180,701
2015																91,347		132,260		175,866
2016																		106,022		155,720
2017																				117,287
																		Total		1,677,641
										All outstanding liabilities before 2008, net of reinsurance										4,158
								Liabilities for loss and loss adjustment expenses, net of reinsurance												464,131

Businessowners' Policies (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	39,660		38,986		39,334		32,974		30,250		29,793		31,066		31,340		30,967		31,065			192		3,258
2009				48,535		51,762		46,645		43,828		43,553		44,938		44,299		44,273		43,933			272		3,474
2010						53,669		49,285		42,408		39,915		40,899		40,581		41,239		41,197			697		3,917
2011								54,469		57,083		51,047		58,242		59,256		58,966		58,456			1,080		4,959
2012										54,342		48,029		46,303		44,172		44,077		43,747			756		5,540
2013												49,617		42,618		41,005		40,624		41,369			3,192		3,479
2014														55,962		60,949		62,548		59,806			5,952		4,054
2015																52,871		53,768		57,245			10,256		3,913
2016																		52,335		53,792			11,938		3,757
2017																				46,624			15,252		3,462
																		Total		477,234

Businessowners' Policies (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	15,019		21,765		24,449		25,738		28,026		28,660		28,589		29,778		30,873		30,873
2009				18,915		29,612		32,689		36,073		40,052		42,895		43,358		43,448		43,547
2010						20,821		28,131		31,027		34,705		37,819		38,900		40,279		40,395
2011								27,884		37,362		41,011		46,444		52,114		55,856		57,045
2012										22,199		31,833		35,089		37,215		38,766		40,627
2013												17,412		26,592		30,845		34,760		37,993
2014														28,914		40,584		44,911		49,460
2015																24,189		36,014		42,710
2016																		24,655		36,848
2017																				21,865
																		Total		401,363
										All outstanding liabilities before 2008, net of reinsurance										7,292
								Liabilities for loss and loss adjustment expenses, net of reinsurance												83,163

Commercial Property (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	97,578		102,860		101,436		101,470		101,265		101,702		101,043		100,881		101,043		101,054			2		7,604
2009				82,619		82,124		82,025		82,014		80,774		80,455		80,558		80,545		80,416			4		7,009
2010						105,647		96,851		97,386		96,127		95,530		95,363		95,178		95,155			5		7,667
2011								136,954		131,667		130,942		131,282		131,353		131,113		131,049			4		9,036
2012										118,464		114,224		115,375		116,658		117,102		117,170			24		8,514
2013												88,101		90,639		90,103		90,005		90,436			42		5,709
2014														141,192		136,249		136,820		138,751			126		6,512
2015																110,270		109,513		111,750			261		6,398
2016																		121,927		126,185			804		6,686
2017																				138,773			8,794		6,358
																		Total		1,130,739

Commercial Property (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	68,211		98,921		100,465		99,288		100,213		100,752		100,908		100,868		101,034		101,032
2009				59,933		78,695		80,433		80,894		80,251		80,352		80,529		80,509		80,405
2010						69,543		91,918		94,602		95,111		95,270		95,147		95,156		95,150
2011								94,538		127,580		129,579		130,681		131,060		131,115		131,089
2012										81,528		108,834		111,503		114,699		116,291		116,625
2013												60,244		87,874		90,446		90,350		90,840
2014														101,131		132,909		136,634		137,883
2015																79,048		106,182		109,829
2016																		83,966		118,789
2017																				99,047
																		Total		1,080,689
										All outstanding liabilities before 2008, net of reinsurance										250
								Liabilities for loss and loss adjustment expenses, net of reinsurance												50,300

Personal Automobile (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	100,311		106,999		106,842		103,934		100,213		99,912		99,686		99,255		99,116		99,270			191		16,042
2009				93,808		103,319		105,033		103,908		104,734		103,866		103,393		103,412		103,348			191		17,346
2010						103,340		110,075		112,346		109,515		107,490		107,405		107,224		107,054			222		20,822
2011								113,232		116,164		113,686		112,993		114,241		113,830		113,988			284		22,700
2012										113,771		114,921		109,832		109,324		110,294		110,300			728		22,332
2013												108,417		109,620		106,225		106,703		107,759			851		22,371
2014														102,250		109,325		106,757		107,452			2,554		22,499
2015																96,387		99,698		100,214			6,541		20,840
2016																		92,727		98,032			11,651		19,747
2017																				101,880			22,284		19,818
																		Total		1,049,297

Personal Automobile (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	50,396		73,194		84,715		91,834		95,932		97,723		98,174		98,604		98,668		98,810
2009				51,039		71,911		86,431		96,229		100,566		102,187		102,322		102,437		103,009
2010						58,786		82,490		95,300		101,540		104,061		105,849		106,453		106,733
2011								61,323		82,102		93,878		105,068		111,085		112,732		113,551
2012										63,704		82,729		94,842		102,977		107,890		109,355
2013												61,384		80,861		92,637		100,528		105,131
2014														62,519		83,739		92,589		99,173
2015																58,725		76,470		87,163
2016																		57,961		76,823
2017																				62,854
																		Total		962,602
										All outstanding liabilities before 2008, net of reinsurance										5,862
								Liabilities for loss and loss adjustment expenses, net of reinsurance												92,557

Homeowners (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																							As of December 31, 2017
Accident Year	Unaudited																						IBNR		Cumulative Number of Reported Claims
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	41,224		41,747		39,342		39,203		38,062		38,410		38,111		38,042		38,045		38,038			56		5,139
2009				47,636		44,511		42,609		40,313		61,927		40,400		40,465		40,457		40,451			73		5,633
2010						68,373		67,525		63,285		97,761		62,462		62,402		62,339		62,392			84		9,131
2011								103,804		98,211		82,744		94,167		94,543		94,183		94,378			159		15,106
2012										87,260		82,745		86,560		86,667		86,271		86,330			180		16,936
2013												73,670		72,528		71,494		72,145		71,714			284		7,747
2014														80,111		82,461		83,637		83,844			1,146		8,762
2015																76,637		76,400		76,559			2,744		7,724
2016																		60,105		60,931			2,067		6,820
2017																				59,167			5,315		6,651
																		Total		673,804

Homeowners (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2008			2009		2010		2011		2012		2013		2014		2015		2016		2017
2008	$	21,277		33,535		36,271		37,086		37,763		37,837		37,933		37,939		37,930		37,928
2009				28,299		36,965		38,078		39,342		39,731		39,819		39,907		40,189		40,269
2010						43,699		58,638		60,295		61,106		62,155		62,227		62,241		62,272
2011								71,668		89,963		91,718		92,185		93,312		93,720		94,007
2012										69,056		79,584		82,720		84,250		85,196		85,562
2013												50,664		65,528		67,838		69,775		71,776
2014														61,561		76,007		79,751		81,664
2015																52,589		70,078		72,202
2016																		42,252		57,333
2017																				45,466
																		Total		648,479
										All outstanding liabilities before 2008, net of reinsurance										5,403
								Liabilities for loss and loss adjustment expenses, net of reinsurance												30,728

E&S Casualty Lines (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance																	As of December 31, 2017
Accident Year	Unaudited																IBNR		Cumulative Number of Reported Claims
	2011			2012		2013		2014		2015		2016		2017
2008	$	92		169		146		119		52		(162	)	119			—		35
2009	885			1,053		938		728		710		96		737			—		274
2010	3,294			4,106		3,369		4,299		3,831		3,055		4,932			—		804
2011	8,127			7,102		9,853		12,207		10,273		9,652		10,228			361		1,316
2012				42,367		42,621		43,175		46,149		46,165		45,988			7,313		2,006
2013						55,468		60,309		67,099		69,112		67,647			15,326		2,219
2014								55,316		63,505		69,929		71,719			18,224		1,987
2015										75,498		76,432		82,404			32,909		2,606
2016												94,451		96,416			65,489		2,454
2017														91,438			79,354		1,760
												Total		471,628

E&S Casualty Lines (in thousands)
Cumulative Paid Loss and Allocated Loss Adjustment Expenses, Net of Reinsurance
Accident Year	Unaudited
	2011			2012		2013		2014		2015		2016		2017
2008	$	—		24		70		80		79		92		97
2009	—			198		431		605		626		709		737
2010	—			1,218		2,570		3,574		4,078		4,513		4,610
2011	—			806		3,200		6,445		9,954		9,912		10,256
2012				3,722		7,914		16,430		25,064		32,343		36,278
2013						2,715		9,470		21,980		35,200		46,108
2014								2,353		12,234		25,571		43,877
2015										3,036		13,057		29,389
2016												3,720		16,195
2017														5,057
												Total		192,604
				All outstanding liabilities before 2008, net of reinsurance										—
				Liabilities for loss and loss adjustment expenses, net of reinsurance										279,023

Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Table Text Block]

(in thousands)	December 31, 2017
Net outstanding liabilities:
Standard Commercial Lines
General liability	1,092,058
Workers compensation	916,471
Commercial automobile	464,131
Businessowners' policies	83,163
Commercial property	50,300
Other Standard Commercial Lines	10,560
Total Standard Commercial Lines net outstanding liabilities	2,616,683
Standard Personal Lines
Personal automobile	92,557
Homeowners	30,728
Other Standard Personal Lines	9,184
Total Standard Personal Lines net outstanding liabilities	132,469
E&S Lines
Casualty lines	279,023
Property lines	13,519
Total E&S Lines net outstanding liabilities	292,542
Total liabilities for unpaid loss and loss adjustment expenses, net of reinsurance	3,041,694
Reinsurance recoverable on unpaid claims:
Standard Commercial Lines
General liability	175,276
Workers compensation	218,024
Commercial automobile	16,745
Businessowners' policies	3,926
Commercial property	24,387
Other Standard Commercial Lines	2,287
Total Standard Commercial Lines reinsurance recoverable on unpaid loss	440,645
Standard Personal Lines
Personal automobile	53,129
Homeowners	999
Other Standard Personal Lines	69,333
Total Standard Personal Lines reinsurance recoverable on unpaid loss	123,461
E&S Lines
Casualty lines	21,360
Property lines	389
Total E&S Lines reinsurance recoverable on unpaid loss	21,749
Total reinsurance recoverable on unpaid loss	585,855
Unallocated loss adjustment expenses	143,691
Total gross liability for unpaid loss and loss adjustment expenses	3,771,240

Short-duration Insurance Contracts, Schedule of Historical Claims Duration [Table Text Block]

Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance
Years	1	2	3	4	5	6	7	8	9	10
General liability	6.6%	12.5	15.4	16.7	14.9	10.1	6.0	4.6	2.2	1.3
Workers compensation	20.2	23.9	13.6	8.3	5.0	3.9	2.8	2.0	1.8	1.9
Commercial automobile	38.2	17.4	14.0	12.8	9.0	4.1	1.6	1.4	0.7	0.1
Businessowners’ policies	46.6	20.8	8.1	7.5	7.5	4.1	2.0	1.6	0.1	1.1
Commercial property	70.5	25.6	2.7	0.7	0.4	0.1	—	—	—	—
Personal automobile	56.1	18.9	10.7	7.4	4.2	1.5	0.4	0.1	0.2	—
Homeowners	71.1	21.0	3.3	2.1	1.6	0.1	—	0.2	0.2	0.1
E&S Lines - casualty	4.5	12.5	18.2	20.4	15.5	8.3	4.0

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