FIGURE D.1 Annual prevalence rate of use of an illegal drug for people ages 12– 17, 1975–1999, National Household Survey of Drug Abuse (NHSDA) and Monitoring the Future (MTF). Note: Annual prevalence measures indicate use of marijuana, cocaine, inhalants, hallucinogens, heroin or nonmedical use of psychotherapeutics at least once during the year.
SOURCES: LD Johnston, PM O’Malley, JG Bachman. (Dec. 1998). Drug use by American young people begins to turn downward. University of Michigan News and Information Services: Ann Arbor, MI. [On_line]. Tables 1b and 3. Available: www.isr.umich.edu/src/mtf; accessed 11/16/99.