The Internal Revenue Service set at 55 cents per mile the 2009 standard deductible rate for using an automobile for business purposes

. After setting 2008 the rate at 50.5 cents, IRS raised to 58.5 cents the rate for the second half of 2008 to account for much higher gasoline prices. "The mileage rates for 2009 reflect generally higher transportation costs compared to a year ago, but the rates also factor in the recent reversal of rising gasoline prices," according to an IRS announcement. "While gasoline is a significant factor in the mileage rate, other fixed and variable costs, such as depreciation, enter the calculation."