Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "Market Groupings, Seasonally Adjusted," in Board of Governors of the Federal Reserve System (U.S.), 1935- and Federal Reserve Board, 1914-1935. "September 1967," Federal Reserve Bulletin (September 1967) : 165-165. https://fraser.stlouisfed.org/title/62/item/21393/toc/350573 , accessed on March 28, 2024.