Board of Governors of the Federal Reserve System (U.S.), 1935-. "Industry Groupings, Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "November 13, 1981," G.12.3 Industrial Production (1981-11-13) : 6-6. https://fraser.stlouisfed.org/title/55/item/59649/toc/472266 , accessed on May 9, 2024.