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-. "August 14, 1981," G.12.3 Industrial Production (1981-08-14) : 5-5. https://fraser.stlouisfed.org/title/55/item/59646/toc/472214 , accessed on May 3, 2024.