Board of Governors of the Federal Reserve System (U.S.), 1935-. "Summary Groupings, 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) : 13-13. https://fraser.stlouisfed.org/title/55/item/59786/toc/470267 , accessed on May 2, 2024.