Board of Governors of the Federal Reserve System (U.S.), 1935-. "Tax - Exempt Debt Securities and Loans, Seasonally Adjusted Annual Rates," in Board of Governors of the Federal Reserve System (U.S.), 1935-. "September 25, 1990 : Annual Revisions," Z.1 Financial Accounts of the United States (1990-09-25) : 56-56. https://fraser.stlouisfed.org/title/93/item/69048/toc/475665 , accessed on April 26, 2024.