Average Federal Tax Rates in 2007: “This page contains CBO’s estimates of average federal tax rates (tax rates as a percentage of income) paid by households in various income categories for the four largest sources of federal revenue – individual income taxes, social insurance (payroll) taxes, corporate income taxes, and excise taxes – as well as the average rate for the four taxes combined. The page also contains estimates of average before- and after-tax household income; the number of households in each income category; shares of taxes, income, and households for each income group; information relating to the methodology used to construct the estimates; supplementary estimates for different types of households; and estimates of the number of households that pay more in payroll taxes than they do in income taxes.”