Total Number of Adults Supervised by the US Correctional System, 2000, 2005, and 2010-2018
"Persons supervised in the community on either probation (3,540,000 persons) or parole (878,000) continued to make up the majority of the correctional population at year-end 2018. Nearly 7 in 10 persons in the correctional population were supervised in the community at year-end 2018 (4,399,000), while 3 in 10 were incarcerated in state or federal prisons or local jails (2,123,100)."
Laura M. Maruschak and Todd D. Minton. Correctional Populations in the United States, 2017-2018. Bureau of Justice Statistics: Washington, DC. August 2020. NCJ252157.