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 14, 1978," G.12.3 Industrial Production (1978-04-14) : 3-3. https://fraser.stlouisfed.org/title/55/item/59605/toc/470370 , accessed on April 30, 2024.