In 2012–2013, 9.52% of US adults used marijuana in the past year, and 2.9% had a diagnosis of DSM-IV marijuana use disorder. Thus, nearly 3 of every 10 marijuana users had a diagnosis of a marijuana use disorder (approximately 6 846 000 Americans). Further, since 2001–2002, the prevalence of adult past-year marijuana use and past-year marijuana use disorders increased markedly; the prevalence of past-year marijuana use more than doubled, while the increase was nearly 2-fold in the prevalence of past-year marijuana use disorder. Because no increase in the risk for marijuana use disorders was found among users (in fact, the risk decreased among users), the increase in prevalence of marijuana use disorders can be attributed to the increase in marijuana users between the 2 surveys.
