Reserve for Loss and Loss Expense

3 Months Ended

Mar. 31, 2024

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


	Quarter ended March 31,
($ 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	688,519		580,408
Prior years	15,773		(12,970)
Total incurred loss and loss expense	704,292		567,438
Paid loss and loss expense for claims occurring in the:
Current year	107,719		91,011
Prior years	435,489		418,194
Total paid loss and loss expense	543,208		509,205
Net reserve for loss and loss expense, at end of period	4,879,394		4,445,541
Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period	622,356		653,909
Gross reserve for loss and loss expense, at end of period	$	5,501,750	5,099,450

Prior year reserve development in First Quarter 2024 was unfavorable by $15.8 million, consisting of $35.0 million of unfavorable casualty reserve development, partially offset by $19.2 million of favorable property reserve development. The unfavorable casualty reserve development was driven by our Standard Commercial Lines segment, which included (i) $50.0

million in our general liability line of business, primarily driven by increased severities in accident years 2020 through 2023, partially offset by (ii) $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 First Quarter 2023 was favorable by $13.0 million, consisting of favorable casualty reserve development of $10.0 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 $2.0 million of unfavorable casualty reserve development in our personal automobile line of business.