Source: Business Cycle Developments, September 1965 And Subsequent Issues. An Alternate Source Is The National Income And Product Accounts Of The United States, 1929-1965; A Supplement To The Survey Of Current Business, August 1966
This NBER data series q09080 appears on the NBER website in Chapter 9 at http://www.nber.org/databases/macrohistory/contents/chapter09.html.
NBER Indicator: q09080
Release: NBER Macrohistory Database
National Bureau of Economic Research, Ratio of Profits (After Taxes) To Income Originating, Corporate, All Industries for United States [Q09080USQ156SNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/Q09080USQ156SNBR/, July 31, 2015.