In an earlier post, I had a graph showing the Historical Tax Rates by Income Group using data from Pitketty & Saez. Here is another graph (found on Greg Mankiw's Blog) which shows historical tax rates by income group but this time the data is from the Congressional Budget Office.

Addendum 3/3/08 The large difference between the two graphs is due to the treatment of payroll taxes paid by employers and the corporate income tax. The Pitketty & Saez data assumes these taxes are actually paid by employees and stockholders but the CBO data in the above graph does not include them.