Segment Information

The disaggregated results of our four reportable segments are used by senior management to manage our operations. These reportable segments are evaluated as follows:


•	Our Standard Commercial Lines, Standard Personal Lines, and E&S Lines are evaluated based on before and after-tax underwriting results (net premiums earned, incurred loss and loss expense, policyholder dividends, policy acquisition costs, and other underwriting expenses), and combined ratios.


•	Our Investments segment is evaluated based on after-tax net investment income and net realized gains and losses.

In computing the results of each segment, we do not make adjustments for interest expense or corporate expenses. We do not maintain separate investment portfolios for the segments and therefore, do not allocate assets to the segments.

The following summaries present revenues (net investment income and net realized and unrealized gains on investments in the case of the Investments segment) and pre-tax income for the individual segments:



Revenue by Segment	Quarter ended September 30,				Nine Months ended September 30,
($ in thousands)	2018			2017	2018		2017
Standard Commercial Lines:
Net premiums earned:
Commercial automobile	$	124,862		111,711	365,197		327,156
Workers compensation	78,784			77,580	237,628		236,366
General liability	154,974			141,059	457,805		422,546
Commercial property	83,056			78,151	245,544		232,594
Businessowners’ policies	25,994			25,019	77,414		74,853
Bonds	8,778			7,420	25,247		20,904
Other	4,608			4,310	13,597		12,839
Miscellaneous income	2,228			1,712	6,936		7,588
Total Standard Commercial Lines revenue	483,284			446,962	1,429,368		1,334,846
Standard Personal Lines:
Net premiums earned:
Personal automobile	42,772			38,612	125,024		113,225
Homeowners	32,293			32,215	96,717		97,382
Other	2,092			1,774	5,349		4,867
Miscellaneous income	310			282	959		938
Total Standard Personal Lines revenue	77,467			72,883	228,049		216,412
E&S Lines:
Net premiums earned:
Casualty lines	42,179			40,090	120,098		117,056
Property lines	13,885			14,114	41,321		41,151
Miscellaneous income	—			—	1		—
Total E&S Lines revenue	56,064			54,204	161,420		158,207
Investments:
Net investment income	52,443			40,446	141,227		119,295
Net realized and unrealized investment (losses) gains	(4,787		)	6,798	(16,988	)	7,487
Total Investments revenue	47,656			47,244	124,239		126,782
Total revenues	$	664,471		621,293	1,943,076		1,836,247



Income Before and After Federal Income Tax	Quarter ended September 30,					Nine Months ended September 30,
($ in thousands)	2018			2017		2018		2017
Standard Commercial Lines:
Underwriting gain, before federal income tax	$	26,333		35,329		74,153		112,634
Underwriting gain, after federal income tax	20,803			22,964		58,581		73,212
Combined ratio	94.5		%	92.1		94.8		91.5

Standard Personal Lines:
Underwriting gain, before federal income tax	$	3,158		8,179		6,457		7,517
Underwriting gain, after federal income tax	2,495			5,316		5,101		4,886
Combined ratio	95.9		%	88.7		97.2		96.5

E&S Lines:
Underwriting gain (loss), before federal income tax	$	3,506		(11,063	)	(4,848	)	(8,174	)
Underwriting gain (loss), after federal income tax	2,770			(7,191	)	(3,830	)	(5,313	)
Combined ratio	93.7		%	120.4		103.0		105.2

Investments:
Net investment income	$	52,443		40,446		141,227		119,295
Net realized and unrealized investment (losses) gains	(4,787		)	6,798		(16,988	)	7,487
Total investment income, before federal income tax	47,656			47,244		124,239		126,782
Tax on investment income	8,562			13,236		21,405		34,572
Total investment income, after federal income tax	$	39,094		34,008		102,834		92,210



Reconciliation of Segment Results to Income Before Federal Income Tax	Quarter ended September 30,					Nine Months ended September 30,
($ in thousands)	2018			2017		2018		2017
Underwriting gain (loss)
Standard Commercial Lines	$	26,333		35,329		74,153		112,634
Standard Personal Lines	3,158			8,179		6,457		7,517
E&S Lines	3,506			(11,063	)	(4,848	)	(8,174	)
Investment income	47,656			47,244		124,239		126,782
Total all segments	80,653			79,689		200,001		238,759
Interest expense	(6,073		)	(6,085	)	(18,350	)	(18,272	)
Corporate expenses	(7,450		)	(6,289	)	(22,065	)	(26,669	)
Income, before federal income tax	$	67,130		67,315		159,586		193,818