WORKERS' COMPENSATION LOSS RESERVES

The following summarizes the activities in the consolidated balance sheets for unpaid claims and claims adjustment expenses within workers' compensation assets and liabilities:



	Year Ended December 31,
(in millions)	2017			2016			2015
Total loss reserves, beginning of year	$	255		$	190		$	148
Incurred
Current year	98			113			89
Prior years	(6		)	28			27
Total incurred	92			141			116
Paid
Current year	(14		)	(14		)	(16		)
Prior years	(78		)	(62		)	(58		)
Total paid	(92		)	(76		)	(74		)
Total loss reserves, end of year	$	255		$	255		$	190

The following summarizes workers' compensation liabilities on the consolidated balance sheets:



(in millions)	December 31, 2017			December 31, 2016
Total loss reserves, end of year	$	255		$	255
Collateral paid to carriers and offset against loss reserves	(23		)	(32		)
Total loss reserves, net of carrier collateral offset	$	232		$	223

Payable in less than 1 year ⁽¹⁾ (net of collateral paid to carriers of $6 and $10 as of December 31, 2017 and 2016, respectively)	67			64
Payable in more than 1 year (net of collateral paid to carriers of $17 and $22 as of December 31, 2017 and 2016, respectively)	165			159
Workers' Compensation Loss Reserves	$	232		$	223

(1) Included under WSE related liabilities within Note 3 to these consolidated financial statements.

Incurred claims related to prior years represent changes in estimates for ultimate losses on workers' compensation claims. For the year ended December 31, 2017, the favorable development was primarily due to lower than expected severity of reported claims associated with office worker WSEs in recent accident years. For the year ended December 31, 2016, the adverse development was primarily due to higher than expected severity of reported claims associated with non-office WSEs in recent accident years. For the year ended December 31, 2015, the adverse development resulted from changes in estimates for ultimate losses associated with non-office WSEs.

As of December 31, 2017 and 2016, we had $63 million and $66 million, respectively, of collateral held by insurance carriers of which $23 million and $32 million was offset against workers' compensation loss reserves as the agreements permit and are net settled of insurance obligations against collateral held.