"At yearend 2020, an estimated 5,500,600 persons were under the supervision of adult correctional systems in the United States, 11% fewer than at the same time the previous year (figure 1).1 This was the first time since 1996 that the total correctional population dropped to less than 5.6 million. About 1 in 47 adult U.S. residents (2.1%) were under some form of correctional supervision at the end of 2020, a decrease from 1 in 40 (2.5%) at the end of 2019."

Source

Rich Kluckow, DSW, and Zhen Zeng, PhD. Correctional Populations in the United States, 2020 - Statistical Tables. Bureau of Justice Statistics: Washington, DC. March 2022. NCJ303184.