17 . leases we lease certain locomotives , freight cars , and other property . the consolidated statements of financial position as of december 31 , 2017 , and 2016 included $ 1635 million , net of $ 953 million of accumulated depreciation , and $ 1997 million , net of $ 1121 million of accumulated depreciation , respectively , for properties held under capital leases . a charge to income resulting from the depreciation for assets held under capital leases is included within depreciation expense in our consolidated statements of income . future minimum lease payments for operating and capital leases with initial or remaining non-cancelable lease terms in excess of one year as of december 31 , 2017 , were as follows : millions operating leases capital leases .
what percentage of total minimum lease payments are capital leases?
approximately 97% ( 97 % ) of capital lease payments relate to locomotives . rent expense for operating leases with terms exceeding one month was $ 480 million in 2017 , $ 535 million in 2016 , and $ 590 million in 2015 . when cash rental payments are not made on a straight-line basis , we recognize variable rental expense on a straight-line basis over the lease term . contingent rentals and sub-rentals are not significant . 18 . commitments and contingencies asserted and unasserted claims 2013 various claims and lawsuits are pending against us and certain of our subsidiaries . we cannot fully determine the effect of all asserted and unasserted claims on our consolidated results of operations , financial condition , or liquidity . to the extent possible , we have recorded a liability where asserted and unasserted claims are considered probable and where such claims can be reasonably estimated . we do not expect that any known lawsuits , claims , environmental costs , commitments , contingent liabilities , or guarantees will have a material adverse effect on our consolidated results of operations , financial condition , or liquidity after taking into account liabilities and insurance recoveries previously recorded for these matters . personal injury 2013 the cost of personal injuries to employees and others related to our activities is charged to expense based on estimates of the ultimate cost and number of incidents each year . we use an actuarial analysis to measure the expense and liability , including unasserted claims . the federal employers 2019 liability act ( fela ) governs compensation for work-related accidents . under fela , damages are assessed based on a finding of fault through litigation or out-of-court settlements . we offer a comprehensive variety of services and rehabilitation programs for employees who are injured at work . our personal injury liability is not discounted to present value due to the uncertainty surrounding the timing of future payments . approximately 95% ( 95 % ) of the recorded liability is related to asserted claims and approximately 5% ( 5 % ) is related to unasserted claims at december 31 , 2017 . because of the uncertainty surrounding the ultimate outcome of personal injury claims , it is reasonably possible that future costs to settle these claims may range from approximately $ 285 million to $ 310 million . we record an accrual at the low end of the range as no amount of loss within the range is more probable than any other . estimates can vary over time due to evolving trends in litigation. .