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-. "August 15, 1969," G.12.3 Industrial Production (1969-08-15) : 3-3. https://fraser.stlouisfed.org/title/55/item/59780/toc/465887 , accessed on May 1, 2024.