During 2012, improvements in our operating results in Canada and the U.K., provided suf ficient positive evidence to  reduce the valuation allowances in those jurisdictions, resulting in tax benefits of  $34 and $20. Deferred tax assets and liabilities —  Temporary differences and carryforwards give rise to the following deferred tax assets and  liabilities. Carryforwards —  Our deferred tax assets include benefits expected from the utilization of net operating loss (NOL), capital  loss and credit carryforwards in the future.  The following table identifies the net operating loss deferred tax asset components  and the related allowances that existed at  December 31, 2014. Due to time limitations on the ability to realize the benefit of the  carryforwards, additional portions of these deferred tax assets may become unrealizable in the future. In addition to the NOL carryforwards listed in the table above, we have deferred tax assets related to capital loss  carryforwards of  $55 which are fully offset with valuation allowances at December 31, 2014.We also have deferred tax assets  of $60 related to other credit carryforwards which are of fset with $57 of valuation allowances at December 31, 2014. The  capital losses can be carried forward indefinitely while the other credits are generally available for  10 to 20 years with portions  currently expiring. We also have a deferred tax asset of  $31 related to NOLs for excess tax benefits generated upon the  settlement of stock awards that increased a current year net operating loss.  We cannot record the benefit of these losses in the  financial statements until the losses are utilized to reduce our income taxes payable at which time we will recognize the tax  benefit in equity. 2014 2013 Net operating loss carryforwards $ 654 $ 788 Postretirement benefits, including pensions 148 123 Research and development costs 110 104 Expense accruals 57 62 Other tax credits recoverable 60 56 Capital loss carryforwards 55 65 Inventory reserves 18 17 Postemployment and other benefits 4 4 Other 25 28 Total 1,131 1,247 Valuation allowance (728) (982) Deferred tax assets 403 265 Unremitted earnings (31) (86) Intangibles (41) (52) Depreciation (39) (39) Other (58) (59) Deferred tax liabilities (169) (236) Net deferred tax assets $ 234 $ 29 Deferred Tax Asset Valuation Allowance Carryforward Period Earliest Year of Expiration Net operating losses U.S. federal $ 432 $ (261) 20 2028 U.S. state 122 (114) Various 2015 Brazil 26 (14) Unlimited France 13 Unlimited Australia 33 (33) Unlimited U.K. 8 (4) Unlimited Argentina 17 (17) 5 2015 Other 3 (3) Unlimited Total $ 654 $ (446) 80