Board of Governors of the Federal Reserve System (U.S.), 1935-. "Market Groupings, Not Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "February 17, 1981," G.12.3 Industrial Production (1981-02-17) : 5-5. https://fraser.stlouisfed.org/title/55/item/59641/toc/472138 , accessed on April 21, 2024.