United States. President and Council of Economic Advisers (U.S.). "Indexes of Output per Man-hour and Related Data, Private Economy," in United States. President and Council of Economic Advisers (U.S.). "1972," Economic Report of the President (1972) : 240-240. https://fraser.stlouisfed.org/title/45/item/8143/toc/290553 , accessed on May 7, 2024.