

($ in thousands)	2019			2018		2017
Gross reserves for loss and loss expense, at beginning of year	$	3,893,868		3,771,240		3,691,719
Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of year	537,388			585,855		611,200
Net reserves for loss and loss expense, at beginning of year	3,356,480			3,185,385		3,080,519
Incurred loss and loss expense for claims occurring in the:
Current year	1,601,780			1,527,997		1,384,266
Prior years	(50,289		)	(29,863	)	(39,192	)
Total incurred loss and loss expense	1,551,491			1,498,134		1,345,074
Paid loss and loss expense for claims occurring in the:
Current year	579,527			573,718		497,486
Prior years	805,443			753,321		742,722
Total paid loss and loss expense	1,384,970			1,327,039		1,240,208
Net reserves for loss and loss expense, at end of year	3,523,001			3,356,480		3,185,385
Add: Reinsurance recoverable on unpaid loss and loss expense, at end of year	544,162			537,388		585,855
Gross reserves for loss and loss expense at end of year	$	4,067,163		3,893,868		3,771,240

Our net loss and loss expense reserves increased by $166.5 million in 2019, $171.1 million in 2018, and $104.9 million in 2017. The loss and loss expense reserves are net of anticipated recoveries for salvage and subrogation claims, which amounted to $76.7 million for 2019, $67.7 million for 2018, and $64.8 million for 2017. The increase in net loss and loss expense reserves in 2019 was primarily driven by increases in exposure due to premium growth. This increase was partially offset by favorable prior year loss development, largely driven by the workers compensation line of business.



(Favorable)/Unfavorable Prior Year Development
($ in millions)	2019			2018		2017
General Liability	$	(5.0	)	(9.5	)	(48.3	)
Commercial Automobile	0.7			36.7		35.6
Workers Compensation	(68.0		)	(83.0	)	(52.3	)
Businessowners' Policies	1.9			(1.5	)	1.9
Commercial Property	5.1			7.5		8.7
Homeowners	7.5			9.8		0.4
Personal Automobile	4.4			3.0		6.7
E&S Casualty Lines	2.0			12.0		10.0
E&S Property Lines	1.0			(4.8	)	0.1
Other	0.1			(0.1	)	(2.0	)
Total	$	(50.3	)	(29.9	)	(39.2	)

The Insurance Subsidiaries had $50.3 million of favorable prior accident year reserve development during 2019, which included $61.0 million of net favorable casualty reserve development and $10.7 million of unfavorable property reserve development. The net favorable casualty reserve development was largely driven by the workers compensation line of business, which was impacted by continued favorable medical trends in accident years 2017 and prior.

The Insurance Subsidiaries had $29.9 million of favorable prior accident year reserve development during 2018, which included $41.5 million of net favorable casualty reserve development and $11.6 million of unfavorable property reserve development. The net favorable casualty reserve development was largely driven by the workers compensation line of business, reflecting continued

favorable medical trends in accident years 2017 and prior. Partially offsetting this net favorable reserve development was $37.5 million of unfavorable casualty reserve development in the commercial auto line of business, driven by increases in frequencies and severities in accident years 2015 through 2017. In addition, our E&S casualty lines experienced unfavorable reserve development of $12.0 million in 2018.

The Insurance Subsidiaries had $39.2 million of favorable prior accident year reserve development during 2017. The net favorable casualty reserve development was largely driven by the workers compensation and general liability lines of business in accident years 2014 and prior. Partially offsetting this net favorable reserve development was $36.0 million of unfavorable casualty reserve development in the commercial automobile line of business, which was primarily driven by accident years 2012 through 2016. In addition, our E&S casualty lines experienced unfavorable reserve development of $10.0 million in 2017, primarily related to accident years 2015 and 2016.

(b) We have exposure to abuse and molestation claims within our general liability line of business through insurance policies that we issue to schools, religious institutions, daycares, and other social services. We also have exposure to abuse and molestation claims from recently enacted state laws that extend the statute of limitations or permit windows to be opened for abuse and molestation claims and lawsuits that were previously barred by statutes of limitations. The emergence of these claims is slow and highly unpredictable. There are significant uncertainties in estimating our exposure to abuse and molestation claims (for both case and IBNR reserves) resulting from (i) lack of relevant historical data, (ii) the delayed and inconsistent reporting patterns associated with these claims, (iii) the obligation of an insurer to defend a claim, (iv) the extent to which a party can prove the existence of coverage, and (v) uncertainty as to the number and identity of claimants. It is possible, as a result, that we may receive claims decades after the allegations occurred from coverages provided by us, including predecessor companies, that will require complex claims coverage determinations, potential litigation, and the need to collect from reinsurers under older reinsurance agreements. We do not discount to present value that portion of our loss and loss expense reserves expected to be paid in future periods.

(c) Reserves established for liability insurance include exposure to asbestos and environmental claims. These claims have arisen primarily from insured exposures in municipal government, small non-manufacturing commercial risk, and homeowners policies. The emergence of these claims is slow and highly unpredictable. There are significant uncertainties in estimating our exposure to asbestos and environmental claims (for both case and IBNR reserves) resulting from lack of relevant historical data, the delayed and inconsistent reporting patterns associated with these claims, and uncertainty as to the number and identity of claimants and complex legal and coverage issues. Legal issues that arise in asbestos and environmental cases include federal or state venue, choice of law, causation, admissibility of evidence, allocation of damages and contribution among joint defendants, successor and predecessor liability, and whether direct action against insurers can be maintained. Coverage issues that arise in asbestos and environmental cases include the interpretation and application of policy exclusions, the determination and calculation of policy limits, the determination of the ultimate amount of a loss, the extent to which a loss is covered by a policy, if at all, the obligation of an insurer to defend a claim, and the extent to which a party can prove the existence of coverage. Courts have reached different and sometimes inconsistent conclusions on these legal and coverage issues. We do not discount to present value that portion of our loss and loss expense reserves expected to be paid in future periods.

Reserves for asbestos and environmental claims are highly uncertain. There are significant uncertainties associated with estimating critical assumptions, such as average clean-up costs, third-party costs, potentially responsible party shares, allocation of damages, litigation and coverage costs, and potential state and federal legislative changes. Estimating IBNR is challenging because of the delayed and inconsistent reporting patterns associated with these claims. Traditional actuarial approaches cannot be applied because past loss history is not necessarily indicative of future behavior. While certain alternative projection models can be applied, such models can produce significantly different results with small changes in assumptions. As a result, reserves for asbestos and environmental require a high degree of judgment. Because of the significant uncertainty in the estimate, we do not calculate an asbestos and environmental loss range.

Historically, our asbestos and environmental claims have been significantly lower in volume than many other standard commercial lines carriers since, prior to the introduction of the absolute pollution exclusion endorsement in the mid-1980’s, we primarily wrote Standard Personal Lines, and therefore, our exposure to asbestos and environmental claims has been limited.



	2019					2018				2017
($ in thousands)	Gross			Net		Gross		Net		Gross		Net
Asbestos
Reserves for loss and loss expense at beginning of year	$	7,328		6,097		7,577		6,346		7,847		6,615
Incurred loss and loss expense	(375		)	(375	)	—		—		—		—
Less: loss and loss expense paid	(665		)	(665	)	(249	)	(249	)	(270	)	(269	)
Reserves for loss and loss expense at the end of year	$	6,288		5,057		7,328		6,097		7,577		6,346

Environmental
Reserves for loss and loss expense at beginning of year	$	22,692		16,686		20,838		14,866		22,115		16,101
Incurred loss and loss expense	723			609		3,059		2,877		126		—
Less: loss and loss expense paid	(1,002		)	(763	)	(1,205	)	(1,057	)	(1,403	)	(1,235	)
Reserves for loss and loss expense at the end of year	$	22,413		16,532		22,692		16,686		20,838		14,866

Total Asbestos and Environmental Claims
Reserves for loss and loss expense at beginning of year	$	30,020		22,783		28,415		21,212		29,962		22,716
Incurred loss and loss expense	348			234		3,059		2,877		126		—
Less: loss and loss expense paid	(1,667		)	(1,428	)	(1,454	)	(1,306	)	(1,673	)	(1,504	)
Reserves for loss and loss expense at the end of year	$	28,701		21,589		30,020		22,783		28,415		21,212

(d) The following is information about incurred and paid claims development as of December 31, 2019, net of reinsurance, as well as cumulative claim frequency and the associated IBNR liabilities. During the experience period, we implemented a series of claims-related initiatives and claims management changes. These initiatives focused on claims handling and reserving, medical claims costs, and loss expenses. As a result of these initiatives, several historical patterns have changed and may no longer be appropriate to use as the sole basis for projections.



All Lines (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	950,114	973,742	977,959	956,600	943,118	922,404	915,131	907,074	904,561	902,258	38,152	94,526
2011			1,042,576	1,061,667	1,062,233	1,056,107	1,033,518	1,023,726	1,019,351	1,013,115	1,013,175	44,453	104,861
2012				1,065,437	1,071,290	1,020,655	998,028	973,089	973,644	973,411	968,536	50,942	104,148
2013					1,044,142	1,062,045	1,047,230	1,021,007	1,002,316	987,763	984,858	72,970	91,326
2014						1,107,513	1,133,798	1,146,990	1,124,014	1,104,218	1,100,208	83,392	95,081
2015							1,114,081	1,130,513	1,144,830	1,138,313	1,119,441	111,657	94,128
2016								1,188,608	1,203,634	1,227,142	1,199,734	205,126	94,579
2017									1,270,110	1,313,372	1,313,585	336,155	98,014
2018										1,413,800	1,461,603	501,519	104,187
2019											1,483,945	759,853	93,947
										Total	11,547,343



All Lines (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	328,826	509,910	625,229	704,895	773,536	803,773	823,770	835,532	846,386	851,633
2011			391,944	585,867	692,730	782,655	852,202	901,801	924,111	940,626	950,836
2012				378,067	555,819	651,544	743,742	810,135	856,195	879,372	898,269
2013					335,956	518,872	644,475	748,758	833,823	872,331	891,841
2014						405,898	614,075	736,154	855,959	936,425	981,868
2015							376,641	581,203	725,385	845,868	929,222
2016								387,272	617,958	764,331	892,390
2017									433,440	678,453	829,134
2018										511,271	779,466
2019											510,091
										Total	8,514,750
						All outstanding liabilities before 2010, net of reinsurance					360,119
					Liabilities for loss and loss expenses, net of reinsurance						3,392,713



General Liability (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	215,208	228,680	242,499	237,154	222,328	211,619	208,968	202,394	206,146	205,322	17,542	12,705
2011			227,769	228,720	239,480	230,785	217,256	211,196	212,011	211,500	213,485	19,913	11,649
2012				238,979	245,561	215,083	194,144	175,305	175,268	180,659	182,085	21,005	9,994
2013					250,609	251,421	239,776	225,709	210,785	203,831	202,697	28,857	10,378
2014						244,312	249,946	257,132	239,333	234,082	237,125	42,388	10,586
2015							254,720	245,710	246,990	233,249	219,204	55,244	10,381
2016								277,214	272,048	277,986	263,245	98,385	10,526
2017									293,747	293,128	301,384	161,114	10,706
2018										317,934	336,326	223,228	10,656
2019											347,150	296,257	8,626
										Total	2,508,023



General Liability (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	15,726	46,201	80,018	113,050	143,360	161,487	172,394	178,179	183,988	185,962
2011			13,924	42,692	73,643	102,978	135,377	159,768	170,525	181,856	187,276
2012				13,030	35,241	56,580	89,008	109,448	130,866	144,451	156,186
2013					12,789	35,113	72,127	104,587	139,114	153,628	163,764
2014						14,901	46,825	79,972	121,969	154,957	179,192
2015							14,665	39,978	78,668	116,804	144,216
2016								15,684	46,549	89,431	133,757
2017									17,366	49,470	92,355
2018										19,531	60,784
2019											18,097
										Total	1,321,589
						All outstanding liabilities before 2010, net of reinsurance					93,982
					Liabilities for loss and loss expenses, net of reinsurance						1,280,416



Workers Compensation (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	198,371	214,469	212,815	211,030	214,916	212,448	208,155	204,423	199,539	197,095	19,514	12,192
2011			205,238	218,973	214,743	215,114	210,591	205,708	200,674	194,821	192,863	22,717	11,860
2012				203,864	208,036	199,360	195,197	188,596	187,359	183,314	178,774	24,605	11,618
2013					199,794	194,318	187,658	173,160	166,662	162,787	159,767	26,260	11,375
2014						199,346	187,065	182,579	172,515	164,420	160,646	28,320	10,495
2015							193,729	194,639	183,604	179,642	176,242	27,927	10,549
2016								196,774	184,946	176,248	166,009	41,146	10,572
2017									195,202	184,306	175,853	53,654	10,793
2018										193,894	193,818	74,399	11,078
2019											188,625	100,336	9,805
										Total	1,789,692



Workers Compensation (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	46,795	93,281	122,442	137,184	149,086	153,795	158,078	162,796	165,526	167,478
2011			42,941	90,836	118,847	134,646	139,232	149,269	154,320	158,535	161,696
2012				40,911	86,909	108,211	122,755	132,052	139,477	143,281	146,739
2013					36,829	74,568	96,376	109,739	118,669	124,130	126,822
2014						35,924	78,944	100,876	113,626	119,392	124,077
2015							33,857	77,320	98,195	112,601	120,097
2016								34,525	78,531	98,037	109,166
2017									40,375	82,216	100,645
2018										41,122	84,780
2019											37,826
										Total	1,179,326
						All outstanding liabilities before 2010, net of reinsurance					240,140
					Liabilities for loss and loss expenses, net of reinsurance						850,505



Commercial Automobile (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	187,562	189,305	187,778	181,923	179,854	172,969	173,157	173,471	173,080	172,995	682	25,512
2011			174,006	183,044	182,325	178,421	172,617	174,882	174,514	173,507	173,401	899	25,524
2012				179,551	191,947	183,527	184,289	184,367	186,128	184,633	185,357	1,920	24,160
2013					188,289	205,282	209,197	207,994	210,410	207,975	209,602	2,928	25,722
2014						200,534	212,725	216,824	219,925	218,172	217,334	4,831	27,714
2015							220,994	240,958	253,074	259,495	260,565	7,966	29,340
2016								255,187	274,367	285,302	285,304	21,279	31,167
2017									301,274	329,389	324,291	57,165	32,474
2018										347,908	352,487	109,922	35,034
2019											385,212	183,477	33,438
										Total	2,566,548



Commercial Automobile (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	68,098	99,254	128,015	146,913	163,513	167,227	169,100	169,793	171,693	171,941
2011			69,849	99,196	121,576	142,507	157,291	166,082	170,000	170,913	172,365
2012				73,316	105,371	127,235	148,669	168,114	176,656	179,501	181,353
2013					76,469	109,893	140,015	169,850	189,626	200,750	202,622
2014						80,810	117,169	148,884	180,701	202,821	209,655
2015							91,347	132,260	175,866	211,515	238,142
2016								106,022	155,720	200,701	233,939
2017									117,287	178,823	220,422
2018										134,867	193,788
2019											149,538
										Total	1,973,765
						All outstanding liabilities before 2010, net of reinsurance					3,904
					Liabilities for loss and loss expenses, net of reinsurance						596,686



Businessowners' Policies (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	53,669	49,285	42,408	39,915	40,899	40,581	41,239	41,197	40,920	41,156	333	3,920
2011			54,469	57,083	51,047	58,242	59,256	58,966	58,456	58,735	58,948	362	4,960
2012				54,342	48,029	46,303	44,172	44,077	43,747	43,418	43,717	703	5,543
2013					49,617	42,618	41,005	40,624	41,369	39,709	39,699	803	3,482
2014						55,962	60,949	62,548	59,806	58,517	58,093	1,390	4,064
2015							52,871	53,768	57,245	55,925	54,454	3,235	3,959
2016								52,335	53,792	54,993	53,835	4,245	3,843
2017									46,624	48,698	51,524	10,252	3,864
2018										55,024	57,202	12,432	4,159
2019											53,531	15,068	3,210
										Total	512,159



Businessowners' Policies (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	20,821	28,131	31,027	34,705	37,819	38,900	40,279	40,395	40,439	40,823
2011			27,884	37,362	41,011	46,444	52,114	55,856	57,045	57,365	57,380
2012				22,199	31,833	35,089	37,215	38,766	40,627	41,326	41,356
2013					17,412	26,592	30,845	34,760	37,993	38,464	39,085
2014						28,914	40,584	44,911	49,460	52,940	55,458
2015							24,189	36,014	42,710	46,571	49,073
2016								24,655	36,848	39,973	45,308
2017									21,865	31,337	36,950
2018										29,995	39,791
2019											27,718
										Total	432,942
						All outstanding liabilities before 2010, net of reinsurance					7,530
					Liabilities for loss and loss expenses, net of reinsurance						86,747



Commercial Property (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR		Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR		Cumulative Number of Reported Claims
2010	$	105,647	96,851	97,386	96,127	95,530	95,363	95,178	95,155	95,142	95,338	4		7,669
2011			136,954	131,667	130,942	131,282	131,353	131,113	131,049	131,009	131,002	7		9,038
2012				118,464	114,224	115,375	116,658	117,102	117,170	117,225	117,220	10		8,517
2013					88,101	90,639	90,103	90,005	90,436	90,278	90,218	18		5,713
2014						141,192	136,249	136,820	138,751	138,155	136,212	33		6,515
2015							110,270	109,513	111,750	111,566	112,496	56		6,404
2016								121,927	126,185	125,937	124,487	(96	)	6,739
2017									138,773	149,106	149,044	(884	)	6,886
2018										183,177	190,834	(329	)	8,240
2019											173,826	15,732		6,722
										Total	1,320,677



Commercial Property (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	69,543	91,918	94,602	95,111	95,270	95,147	95,156	95,150	95,138	95,334
2011			94,538	127,580	129,579	130,681	131,060	131,115	131,089	131,100	131,092
2012				81,528	108,834	111,503	114,699	116,291	116,625	116,671	116,674
2013					60,244	87,874	90,446	90,350	90,840	90,696	90,646
2014						101,131	132,909	136,634	137,883	137,418	136,008
2015							79,048	106,182	109,829	110,994	110,969
2016								83,966	118,789	122,930	123,828
2017									99,047	142,338	148,589
2018										135,416	184,813
2019											130,891
										Total	1,268,844
						All outstanding liabilities before 2010, net of reinsurance					237
					Liabilities for loss and loss expenses, net of reinsurance						52,071



Personal Automobile (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	103,340	110,075	112,346	109,515	107,490	107,405	107,224	107,054	106,887	106,785	64	20,823
2011			113,232	116,164	113,686	112,993	114,241	113,830	113,988	113,921	114,056	121	22,700
2012				113,771	114,921	109,832	109,324	110,294	110,300	109,795	109,701	155	22,332
2013					108,417	109,620	106,225	106,703	107,759	107,680	107,916	348	22,375
2014						102,250	109,325	106,757	107,452	106,821	107,104	307	22,506
2015							96,387	99,698	100,214	99,570	98,718	742	20,863
2016								92,727	98,032	100,202	101,140	2,565	19,819
2017									101,880	105,139	103,653	6,342	20,725
2018										111,594	113,569	14,259	22,621
2019											114,043	25,832	21,988
										Total	1,076,685



Personal Automobile (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	58,786	82,490	95,300	101,540	104,061	105,849	106,453	106,733	106,722	106,716
2011			61,323	82,102	93,878	105,068	111,085	112,732	113,551	113,664	113,856
2012				63,704	82,729	94,842	102,977	107,890	109,355	109,447	109,482
2013					61,384	80,861	92,637	100,528	105,131	106,679	106,876
2014						62,519	83,739	92,589	99,173	104,055	105,709
2015							58,725	76,470	87,163	92,102	95,997
2016								57,961	76,823	86,752	94,372
2017									62,854	82,730	91,479
2018										69,721	89,628
2019											69,699
										Total	983,814
						All outstanding liabilities before 2010, net of reinsurance					7,462
					Liabilities for loss and loss expenses, net of reinsurance						100,331



Homeowners (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year	Unaudited											IBNR	Cumulative Number of Reported Claims
Accident Year	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	68,373	67,525	63,285	61,927	62,462	62,402	62,339	62,392	62,402	62,380	48	9,132
2011			103,804	98,211	97,761	94,167	94,543	94,183	94,378	94,587	94,572	82	15,111
2012				87,260	82,744	86,560	86,667	86,271	86,330	86,483	86,567	94	16,941
2013					73,670	72,528	71,494	72,145	71,714	72,148	72,318	420	7,749
2014						80,111	82,461	83,637	83,844	83,539	83,824	682	8,773
2015							76,637	76,400	76,559	74,723	74,978	660	7,746
2016								60,105	60,931	62,391	61,723	1,221	6,885
2017									59,167	67,978	70,365	2,500	7,370
2018										62,961	68,526	2,366	7,554
2019											64,306	6,299	6,468
										Total	739,559



Homeowners (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year	Unaudited
	2010		2011	2012	2013	2014	2015	2016	2017	2018	2019
2010	$	43,699	58,638	60,295	61,106	62,155	62,227	62,241	62,272	62,283	62,329
2011			71,668	89,963	91,718	92,185	93,312	93,720	94,007	94,412	94,458
2012				69,056	79,584	82,720	84,250	85,196	85,562	85,642	85,897
2013					50,664	65,528	67,838	69,775	71,776	72,197	72,433
2014						61,561	76,007	79,751	81,664	82,583	82,836
2015							52,589	70,078	72,202	72,927	74,079
2016								42,252	57,333	59,546	60,082
2017									45,466	63,290	67,193
2018										49,430	64,137
2019											49,680
										Total	713,124
						All outstanding liabilities before 2010, net of reinsurance					5,316
					Liabilities for loss and loss expenses, net of reinsurance						31,752



E&S Casualty Lines (in thousands, except for claim counts)
Incurred Loss and Allocated Loss Expenses, Net of Reinsurance												As of December 31, 2019
Accident Year			Unaudited									IBNR	Cumulative Number of Reported Claims
Accident Year	2011		2012		2013	2014	2015	2016	2017	2018	2019	IBNR	Cumulative Number of Reported Claims
2010	$	3,294	$	4,106	3,369	4,299	3,831	3,055	4,932	5,168	5,534	—	815
2011	8,127		7,102		9,853	12,207	10,273	9,652	10,228	12,119	11,554	177	1,332
2012			42,367		42,621	43,175	46,149	46,165	45,988	46,444	44,622	2,474	2,045
2013					55,468	60,309	67,099	69,112	67,647	68,972	68,451	13,816	2,280
2014						55,316	63,505	69,929	71,719	71,206	71,153	5,559	2,071
2015							75,498	76,432	82,404	90,488	90,355	15,752	2,799
2016								94,451	96,416	104,655	105,120	35,987	2,859
2017									91,438	95,783	99,866	47,074	2,614
2018										98,324	103,004	62,754	2,392
2019											117,087	103,146	1,679
										Total	716,746



E&S Casualty Lines (in thousands)
Cumulative Paid Loss and Allocated Loss Expenses, Net of Reinsurance
Accident Year			Unaudited
Accident Year	2011		2012		2013	2014	2015	2016	2017	2018	2019
2010	$	—	$	1,218	2,570	3,574	4,078	4,513	4,610	4,908	5,362
2011	—		806		3,200	6,445	9,954	9,912	10,256	9,819	9,604
2012			3,722		7,914	16,430	25,064	32,343	36,278	38,298	39,832
2013					2,715	9,470	21,980	35,200	46,108	51,142	54,974
2014						2,353	12,234	25,571	43,877	53,780	60,092
2015							3,036	13,057	29,389	50,712	64,529
2016								3,720	16,195	33,950	56,581
2017									5,057	14,672	34,179
2018										5,509	21,337
2019											4,422
										Total	350,912
						All outstanding liabilities before 2010, net of reinsurance					109
						Liabilities for loss and loss expenses, net of reinsurance					365,943

In 2011, the Parent purchased Mesa Underwriters Specialty Insurance Company ("MUSIC"), a wholly-owned E&S Lines subsidiary of Montpelier Re Holdings, Ltd. Under the terms of the purchase agreement, the Parent acquired net loss and loss reserves amounting to approximately $15 million. All development on this acquired business was fully reinsured as of the acquisition date.



(in thousands)	December 31, 2019
Net outstanding liabilities:
Standard Commercial Lines
General liability	$	1,280,416
Workers compensation	850,505
Commercial automobile	596,686
Businessowners' policies	86,747
Commercial property	52,071
Other Standard Commercial Lines	9,399
Total Standard Commercial Lines net outstanding liabilities	2,875,824

Standard Personal Lines
Personal automobile	100,331
Homeowners	31,752
Other Standard Personal Lines	10,664
Total Standard Personal Lines net outstanding liabilities	142,747

E&S Lines
Casualty lines	365,943
Property lines	8,199
Total E&S Lines net outstanding liabilities	374,142

Total liabilities for unpaid loss and loss expenses, net of reinsurance	3,392,713

Reinsurance recoverable on unpaid claims:
Standard Commercial Lines
General liability	195,830
Workers compensation	206,414
Commercial automobile	14,352
Businessowners' policies	3,012
Commercial property	26,526
Other Standard Commercial Lines	9,113
Total Standard Commercial Lines reinsurance recoverable on unpaid loss	455,247

Standard Personal Lines
Personal automobile	44,104
Homeowners	1,182
Other Standard Personal Lines	28,993
Total Standard Personal Lines reinsurance recoverable on unpaid loss	74,279

E&S Lines
Casualty lines	14,319
Property lines	317
Total E&S Lines reinsurance recoverable on unpaid loss	14,636

Total reinsurance recoverable on unpaid loss	544,162

Unallocated loss expenses	130,288

Total gross liability for unpaid loss and loss expenses	$	4,067,163

(f) The table below reflects the historical average annual percentage payout of incurred claims by age. For example, the general liability line of business averages payout of 6.3% of its ultimate losses in the first year, 12.5% in the second year, and so forth. The following is supplementary information about average historical claims duration as of December 31, 2019:



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	6.3%	12.5	15.5	17.0	14.2	9.8	5.6	4.9	2.8	1.9
Workers compensation	21.9	24.9	13.2	8.2	4.9	4.6	2.3	2.4	1.6	1.1
Commercial automobile	37.8	17.0	14.4	12.9	9.8	4.1	1.3	0.9	1.1	0.1
Businessowners’ policies	47.9	19.5	8.2	8.8	6.6	3.9	2.0	0.8	0.8	0.8
Commercial property	70.6	25.4	2.8	0.8	0.3	0.1	—	—	—	—
Personal automobile	58.2	18.4	9.9	6.8	4.2	1.5	0.5	0.3	0.1	0.1
Homeowners	72.2	20.3	3.3	1.5	1.6	0.4	0.3	0.2	0.1	0.1
E&S Lines - casualty	4.9	12.2	18.1	22.6	14.9	9.4	6.4	3.5	2.0