From the Introduction: "Health insurance is a means for financing a person's health care expenses. While the majority of people have private health insurance, primarily through an employer, many others obtain coverage through programs offered by state and federal governments. Other individuals do not have health insurance coverage at all. [...] This report presents estimates of health insurance coverage in the United States in 2020, a year in which the nation experienced an economic recession related to the COVID-19 [coronavirus disease 2019] global pandemic. The statistics in this report are based on information collected in the Current Population Survey Annual Social and Economic Supplement (CPS ASEC)."
U.S. Census Bureau: https://www.census.gov/