Of the 3,789,800 adults on probation in the US at the end of 2015, 25% (approximately 947,450 people) had a drug charge as their most serious offense.

"The decline in the U.S. correctional population from January 1, 2016 (6,676,200 persons), to December 31, 2016 (6,613,500), continued a downward trend that began in 2008 (table 1). Persons supervised in the community on either probation (3,673,100 persons) or parole (874,800) continued to account for the majority of the U.S. correctional population at year-end 2016. Nearly 7 in 10 persons under correctional supervision were supervised in the community (4,537,100) on December 31, 2016, and 3 in 10 (2,162,400) were incarcerated in state or federal prisons or local jails.¹