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-. "February 15, 1980," G.12.3 Industrial Production (1980-02-15) : 4-4. https://fraser.stlouisfed.org/title/55/item/59629/toc/471917 , accessed on April 24, 2024.