Board of Governors of the Federal Reserve System (U.S.), 1935-. "Summary Groupings, Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "August 14, 1987," G.12.3 Industrial Production (1987-08-14) : 14-14. https://fraser.stlouisfed.org/title/55/item/59722/toc/473857 , accessed on April 25, 2024.