Note 3. Leases

We lease certain assets under operating leases, which primarily consist of real estate leases for 45 of our 225 service center locations at December 31, 2015. Certain operating leases provide for renewal options, which can vary by lease and are typically offered at their fair rental value. We have not made any residual value guarantees related to our operating leases; therefore, we have no corresponding liability recorded on our Balance Sheets.

Future minimum annual lease payments for assets under operating leases as of December 31, 2015 are as follows:



(In thousands)	Total
2016	$	13,761
2017	10,239
2018	6,937
2019	4,424
2020	3,677
Thereafter	26,868
	$	65,906

Aggregate expense under operating leases was $15.2 million, $16.5 million and $17.9 million for 2015, 2014 and 2013, respectively. Certain operating leases include rent escalation provisions, which we recognize as expense on a straight-line basis.

At December 31, 2015, we leased certain information systems under capital leases with a gross carrying value of $3.6 million and accumulated amortization of $0.4 million. We did not have any assets under capital leases at December 31, 2014.