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-. "April 14, 1978," G.12.3 Industrial Production (1978-04-14) : 5-5. https://fraser.stlouisfed.org/title/55/item/59605/toc/470371 , accessed on April 26, 2024.