Reserve for Loss and Loss Expense

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



	Quarter ended March 31,
($ in thousands)	2018			2017
Gross reserve for loss and loss expense, at beginning of year	$	3,771,240		3,691,719
Less: reinsurance recoverable on unpaid loss and loss expense, at beginning of year	585,855			611,200
Net reserve for loss and loss expense, at beginning of year	3,185,385			3,080,519
Incurred loss and loss expense for claims occurring in the:
Current year	388,801			331,331
Prior years	(3,860		)	(13,859	)
Total incurred loss and loss expense	384,941			317,472
Paid loss and loss expense for claims occurring in the:
Current year	79,345			54,708
Prior years	248,738			235,742
Total paid loss and loss expense	328,083			290,450
Net reserve for loss and loss expense, at end of period	3,242,243			3,107,541
Add: Reinsurance recoverable on unpaid loss and loss expense, at end of period	549,837			571,930
Gross reserve for loss and loss expense at end of period	$	3,792,080		3,679,471

The $57.5 million increase in current year loss and loss expense incurred illustrated in the table above was driven by catastrophe losses and non-catastrophe property losses. Catastrophe losses, which increased $13.8 million, to $26.0 million in First Quarter 2018, were primarily related to the winter storms that impacted the east coast of the United States in early January and several Nor'easters in March. Non-catastrophe property losses, which increased $34.3 million, to $105.7 million in First Quarter 2018, were principally related to the early January deep freeze in our footprint states and a relatively large number of severe fire losses.

Prior year development in First Quarter 2018 of $3.9 million included $8.0 million of favorable casualty development and $4.1 million of unfavorable property development. The favorable casualty development included $16.0 million of development in our workers compensation line of business, partially offset by $8.0 million of unfavorable casualty reserve development in our commercial automobile line of business.

Prior year development in First Quarter 2017 of $13.9 million was primarily due to favorable casualty reserve development of $22.4 million in our general liability line of business. This was partially offset by unfavorable casualty reserve development of $6.0 million in our commercial automobile line of business.

For a discussion of the trends and recent developments impacting these lines, refer to the "Critical Accounting Policies and Estimates" section of Item 7. "Management's Discussion and Analysis of Financial Condition and Results of Operations." in our 2017 Annual Report.