Contingencies

Roper, in the ordinary course of business, is the subject of, or a party to, various pending or threatened legal actions, including product liability and employment practices that, in general, are based upon claims of the kind that have been customary over the past several years and which the Company is vigorously defending. After analyzing the Company's contingent liabilities on a gross basis and, based upon past experience with resolution of its product liability and employment practices claims and the limits of the primary, excess, and umbrella liability insurance coverages that are available with respect to pending claims, management believes that adequate provision has been made to cover any potential liability not covered by insurance, and that the ultimate liability, if any, arising from these actions should not have a material adverse effect on Roper's consolidated financial position, results of operations or cash flows.

Roper or its subsidiaries have been named defendants along with numerous industrial companies in asbestos-related litigation claims in certain U.S. states. No significant resources have been required by Roper to respond to these cases and Roper believes it has valid defenses to such claims and, if required, intends to defend them vigorously. Given the state of these claims it is not possible to determine the potential liability, if any.

Roper's rent expense was $58.6 million, $44.9 million and $40.2 million for 2017, 2016 and 2015, respectively. Roper's future minimum property lease commitments are as follows (in millions):



2018	$	54.3
2019	44.7
2020	39.6
2021	34.6
2022	25.7
Thereafter	58.0
Total	$	256.9

A summary of the Company's warranty accrual activity is presented below (in thousands):



	2017			2016			2015
Balance, beginning of year	$	10,548		$	10,183		$	9,537
Additions charged to costs and expenses	10,820			15,950			14,284
Deductions	(11,170		)	(15,513		)	(13,059		)
Other	389			(72		)	(579		)
Balance, end of year	$	10,587		$	10,548		$	10,183

Other included warranty balances at acquired businesses at the dates of acquisition, the effects of foreign currency translation adjustments, reclassifications and other.

As of December 31, 2017, Roper had $75.9 million of letters of credit issued to guarantee its performance under certain services contracts or to support certain insurance programs and $573.4 million of outstanding surety bonds. Certain contracts, primarily those involving public sector customers, require Roper to provide a surety bond as a guarantee of its performance of contractual obligations.