Board of Governors of the Federal Reserve System (U.S.), 1935-. "Trade Credit, Seasonally Adjusted Annual Rates," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "September 5, 1979 : Annual Revisions," Z.1 Financial Accounts of the United States (1979-09-05) : 54-54. https://fraser.stlouisfed.org/title/93/item/69130/toc/479861 , accessed on December 10, 2023.