Board of Governors of the Federal Reserve System (U.S.), 1935-. "Information Status for Preliminary Estimates," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "August 24, 1981 : Annual Revisions," Z.1 Financial Accounts of the United States (1981-08-24) : 6-8. https://fraser.stlouisfed.org/title/93/item/69066/toc/480985 , accessed on April 17, 2024.