Historical Effective Federal Tax Rates: 1979 to 2006
"The following tables update the Congressional Budget Office’s (CBO’s) estimates
of historical effective tax rates—that is, households’ tax liability divided by their
income—for various income categories.1 These new tables incorporate estimates
for an additional calendar year, 2006, for the four largest sources of federal
revenues—individual income taxes, social insurance (payroll) taxes, corporate
income taxes, and excise taxes—as well as the total effective rate for the four
taxes combined. The tables also present average before-tax and after-tax
household income; counts of households; and shares of taxes, income, and
households for each fifth (quintile) of the income distribution and for the top
percentiles of households..."