Reserve for Loss and Loss Expense

6 Months Ended

Jun. 30, 2024

Insurance Loss Reserves [Abstract]

Reserve for Loss and Loss Expense

Reserve for Loss and Loss Expense

The table below provides a roll forward of the reserve for loss and loss expense for beginning and ending reserve balances:

	Six Months ended June 30,
($ in thousands)	2024		2023
Gross reserve for loss and loss expense, at beginning of period	$	5,336,911	5,144,821
Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of period	618,601		757,513
Net reserve for loss and loss expense, at beginning of period	4,718,310		4,387,308
Incurred loss and loss expense for claims occurring in the:
Current year	1,442,719		1,221,635
Prior years	187,121		(8,067)
Total incurred loss and loss expense	1,629,840		1,213,568
Paid loss and loss expense for claims occurring in the:
Current year	347,501		320,026
Prior years	753,658		720,314
Total paid loss and loss expense	1,101,159		1,040,340
Net reserve for loss and loss expense, at end of period	5,246,991		4,560,536
Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period	656,534		616,487
Gross reserve for loss and loss expense, at end of period	$	5,903,525	5,177,023

Prior year reserve development in Six Months 2024 was unfavorable by $187.1 million, consisting of $211.0 million of unfavorable casualty reserve development, partially offset by $23.9 million of favorable property reserve development. The unfavorable casualty reserve development was driven by our Standard Commercial Lines segment, which included (i) $216.0 million in our general liability line of business, primarily driven by increased severities in accident years 2020 through 2023, (ii) $10.0 million in our commercial automobile line of business, partially offset by (iii) $15.0 million of favorable casualty reserve development in our workers compensation line of business.

Additionally, in our Standard Personal Lines segment, we had unfavorable casualty reserve development of $5.0 million in our personal automobile line of business, offset by favorable development of $5.0 million in our homeowners line of business.

Prior year reserve development in Six Months 2023 was favorable by $8.1 million, consisting of $16.5 million of favorable casualty reserve development, partially offset by $8.4 million of unfavorable property reserve development. The favorable casualty reserve development included $17.5 million in our workers compensation line of business and $5.0 million in our Excess and Surplus ("E&S") casualty lines of business, partially offset by $6.0 million of unfavorable casualty reserve development in our personal automobile line of business.