Board of Governors of the Federal Reserve System (U.S.), 1935-. "Market Groupings, Not Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "May 16, 1969," G.12.3 Industrial Production (1969-05-16) : 4-4. https://fraser.stlouisfed.org/title/55/item/59591/toc/465874 , accessed on April 24, 2024.