United States. Bureau of Economic Analysis. "Gross Domestic Product, 4th Quarter and Year 2020 (Advance Estimate) : Effects of Selected Federal Pandemic Response Programs on Federal Government Receipts and Expenditures, BEA 21-02," Bureau of Economic Analysis (BEA) News Releases (January 28, 2021). https://fraser.stlouisfed.org/title/6148/item/600347/content/pdf/bea_newsreleases_20210128_effects-gov-4thQand2020, accessed on March 24, 2025.