On April 1, the Internal Revenue Service (IRS) released the calendar year 2013 inflation adjustment factors for Indian coal, refined coal, and renewable energy production; the factors are used to determine the availability of credits for these energy sources. The factor for certain energy sources and coal is 1.5063 while the factor for Indian coal is 1.1538. In addition, the IRS reported the reference price for wind electricity is 4.53 cents per kilowatt hour and the reference price for fuel used as feedstock is $58.23 per ton.