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-. "October 15, 1974," G.12.3 Industrial Production (1974-10-15) : 4-4. https://fraser.stlouisfed.org/title/55/item/59797/toc/471560 , accessed on April 25, 2024.