From my book An Illustrated Guide to Income, I examine the changes in tax rates for the highest incomes in the US. The top graph shows the average tax rate since the 1940s for the Top 0.01% of income earners (in 2010, the approximately 15,000 returns reporting more than $8 million dollars in income).
The bottom graph (based on my popular Tax Rates poster) gives an overview of the different "income" taxes in the United States by illustrating the marginal tax rate* for individuals, corporations and capital gains from the sale of stocks or real estate. You can see how the decrease in these top rates (especially the capital gains tax rate) mirror the decrease in the average rate for very high income earners.
*The top tax rate or marginal tax rate is the rate you pay on the “last dollar” you earn; but when you view the taxes you paid as a percentage of your income, your effective tax rate is less than your marginal rate, especially after you take into account the deductions and exemptions, i.e. income that is not subject to any tax.
Graphs created using OmniGraphSketcher and annotated in Illustrator.
Data from the following:
Citizens for Tax Justice. “Top Federal Income Tax Rates Since 1913.” November 2011. http://www.ctj.org/pdf/regcg.pdf.
Hungerford, Thomas L. “Taxes and the Economy: An Economic Analysis of the Top Tax Rates Since 1945.” Congressional Research Service, Report no. R42729. September 12, 2012. http://www.fas.org/sgp/crs/misc/R42729.pdf.
Tax Foundation. “Federal Individual Income Tax: Exemptions and Treatment of Dividends, 1913–2006.” Spring 2012. http://taxfoundation.org/article/federal-individual-income-tax-exemptions-and-treatment-dividends-1913-2006.
Tax Policy Center. “Historical Corporate Top Tax Rate and Bracket.” Spring 2012. http://www.taxpolicycenter.org/taxfacts/displayafact.cfm?Docid=65.
———. “Historical Individual Income Tax Parameters.” Spring 2012. http://www.taxpolicycenter.org/taxfacts/displayafact.cfm?DocID=543&Topic2id=30&Topic3id=39.