While the chart above tracking drug use by youths includes marijuana, the annual Monitoring the Future study performed by the University of Michigan noticed the following:
When marijuana is removed from the list of illicit drugs, far fewer students report use of any of the other drugs included in the index (for 12th graders, these include hallucinogens, cocaine, crack and heroin, as well as use of any of the psychotherapeutic drugs—amphetamines, sedatives, tranquilizers or narcotics other than heroin— taken without medical supervision; for 8th and 10th graders, sedatives and narcotics other than heroin are not included). In 2013, 6 percent, 11 percent and 17 percent of the students in the three grades, respectively, report using any of these other drugs. Those percentages have dropped gradually since around 1996 or 1997, but without further decline in 2013.