This procedure sets forth the 2013 cost-of-living adjustments to certain items due to inflation, and certain items specified in the American Taxpayer Relief Act of 2012, Pub. L. No. 112-240 (ATRA), that are not adjusted for inflation in 2013. This procedure also modifies and supersedes Rev. Proc. 2011-52, 2011-45 I.R.B. 701, to reflect a statutory amendment to section 132(f)(2) made by ATRA effective for 2012.