Board of Governors of the Federal Reserve System (U.S.), 1935-. "Selected Measures of Nonfinancial Business Activity," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "1970-1979," Annual Statistical Digest (March 1981) : 330-335. https://fraser.stlouisfed.org/title/7/item/23506/toc/190729 , accessed on April 23, 2024.