United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services, January 2021 : Highlights (Annual): 2020 Trade Gap is $681.7 Billion, BEA 21-08, CB 21-33,"
Bureau of Economic Analysis (BEA) News Releases
(March 5, 2021).
https://fraser.stlouisfed.org/title/6148/item/600865/content/pdf/bea_newsreleases_20210305_highlights-annual, accessed on June 23, 2025.