The first sentence in the Wikipedia article cites a link (citation #1) to https://nces.ed.gov/pubs2019/2019179.pdf https://nces.ed.gov/pubs2019/2019179.pdf "Rep

The first sentence in the Wikipedia article cites a link (citation #1) to https://nces.ed.gov/pubs2019/2019179.pdf https://nces.ed.gov/pubs2019/2019179.pdf "Report on Adult Literacy in the United States" published in July 2019. This is a two-page PDF that describes the survey, literacy levels, and has links to additional references. The second Wikipedia citation is to a Forbes article.