There continues to be a substantial body of drugged driving research describing the increasing rates of drug involvement among drivers on U.S. roadways. Self-reported data from 2019, showed 28.7 million U.S. drivers ages 16 and older drove under the influence: 13.6 million drove under the influence of illicit drugs, and 12.8 million specifically drove under the influence of marijuana. Drugged driving was most prevalent among driver ages 21–25 (12.7 percent) and ages 16–20 (9.4 percent).