Original Source: St. Louis Federal Reserve Bank, FRED® Economic Data, "Graph: Federal Government: Tax Receipts on Corporate Income (FCTAX)/(Corporate Profits After Tax (CP)+Federal Government: Tax Receipts on Corporate Income (FCTAX))"
Weblink: http://research.stlouisfed.org/fred2/graph/?g=aWA

See also original wikiupload by: Cupco
Weblink: http://commons.wikimedia.org/wiki/File%3AUS_effective_corp_tax_rate_1947-2012.png

Based on: Between The Balance Sheets blog, where graph was created "by combining the Corporate Profits After Tax data from the NIPA tables with the OMB’s data on the revenue collected by the corporate profit tax. The sum of these two series ought to equal total pre-tax profits (roughly), so from there it is easy to calculate the average effective tax rate." Compare to this FRED graph of identical annual data.
Weblink: http://betweenthebalancesheets.wordpress.com/2011/10/06/a-few-issues-with-u-s-corporate-tax-policy/

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