United States. Bureau of Economic Analysis. "Personal Income and Outlays, December 2020 : Historical Comparisons, BEA 21-03," Bureau of Economic Analysis (BEA) News Releases (January 29, 2021). https://fraser.stlouisfed.org/title/6148/item/600353/content/pdf/bea_newsreleases_20210129_historical, accessed on June 20, 2025.