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-. "May 16, 1977," G.12.3 Industrial Production (1977-05-16) : 8-8. https://fraser.stlouisfed.org/title/55/item/59603/toc/470195 , accessed on May 3, 2024.