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 13, 1966," G.12.3 Industrial Production (1966-05-13) : 4-4. https://fraser.stlouisfed.org/title/55/item/59590/toc/487572 , accessed on April 19, 2024.