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-. "May 16, 1978," G.12.3 Industrial Production (1978-05-16) : 13-13. https://fraser.stlouisfed.org/title/55/item/59610/toc/470384 , accessed on April 23, 2024.