Board of Governors of the Federal Reserve System (U.S.), 1935-. "Industry Groupings, Not Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "December 14, 1977," G.12.3 Industrial Production (1977-12-14) : 6-6. https://fraser.stlouisfed.org/title/55/item/59786/toc/470276 , accessed on April 19, 2024.