Board of Governors of the Federal Reserve System (U.S.), 1935-. "Diffusion Indexes," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "November 14, 1980," G.12.3 Industrial Production (1980-11-14) : 14-14. https://fraser.stlouisfed.org/title/55/item/59638/toc/472076 , accessed on April 18, 2024.