United States. President and Council of Economic Advisers (U.S.). "Chain-Type Quantity Indexes for Gross Domestic Product," in United States. President and Council of Economic Advisers (U.S.). "1999," Economic Report of the President (1999) : 340-341. https://fraser.stlouisfed.org/title/45/item/8098/toc/401228 , accessed on April 18, 2024.