Figure 9.1 is titled "Past Month Marijuana Use among Youths Aged 12 to 17: 1971 through 2004." It is a line graph, where the study year is shown on the horizontal axis and the percentage using marijuana in the past month is shown on the vertical axis. There is a note below the graph that reads, "Data points represents surveys conducted since 1971. The 1971 through 1998 data are from NHSDA (PAPI), the 1999 through 2001 data are from NHSDA (CAI), and the 2002 through 2004 data are from NSDUH (CAI). The three series of NSDUH/NHSDA data use different methodologies and are not comparable with the other series. MTF data are average estimates for 8th and 10th graders for 1991 through 2004." The graph has a line for Monitoring the Future (MTF) estimates for 8th and 10th graders, and a line for NSDUH data for 12 to 17 year olds, which is broken into three sections based on the methodology of the survey.
Using a PAPI questionnaire, NHSDA shows that past month marijuana use among youths was 5.1 percent in 1971, which increased to 14.2 percent in 1979. Past month marijuana use then decreased to 3.4 percent in 1991 and increased again to 8.3 percent in 1998. In 1999, using a CAI questionnaire, NHSDA shows that past month marijuana use among youths was 7.2 percent. This increased slightly to 8.0 percent in 2001. In 2002, still using CAI questionnaires, NSDUH showed that past month marijuana use among youths was 8.2 percent. This decreased slightly to 7.6 percent in 2004.
Rates of past month marijuana use are higher for 8th and 10th graders using MTF data than they are for 12 to 17 year olds using NSDUH data.
MTF shows that past month marijuana use among 8th and 10th graders increased from 6.0 percent in 1991 to peak at 15.5 percent in 1997. Rates decreased to 11.2 percent in 2004.
Back to Figure 9.1
This page was last updated on May 20, 2008.