Board of Governors of the Federal Reserve System (U.S.), 1935-. "Market Groupings, Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "April 15, 1974," G.12.3 Industrial Production (1974-04-15) : 3-3. https://fraser.stlouisfed.org/title/55/item/59538/toc/471511 , accessed on May 1, 2024.