Board of Governors of the Federal Reserve System (U.S.), 1935-. "Data Availability for Preliminary Estimates: 1988. Q1," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "June 7, 1988," Z.1 Financial Accounts of the United States (1988-06-07) : 6-7. https://fraser.stlouisfed.org/title/93/item/69049/toc/484176 , accessed on April 24, 2024.