United States. Bureau of Economic Analysis. "U.S. International Trade in Goods and Services, August 2021 : Highlights: August 2021 Trade Gap is $73.3 Billion, BEA 21-50, CB 21-158," Bureau of Economic Analysis (BEA) News Releases (October 5, 2021). https://fraser.stlouisfed.org/title/6148/item/607770/content/pdf/bea_newsreleases_20211005_highlights, accessed on March 25, 2025.