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-. "May 15, 1973," G.12.3 Industrial Production (1973-05-15) : 9-9. https://fraser.stlouisfed.org/title/55/item/59775/toc/471414 , accessed on May 2, 2024.