Overall, the 2005 Monitoring the Future (MTF) survey showed good news. While there was no substantive change in any illicit drug use between 2004 and 2005, analysis of the survey revealed an almost 19 percent decline in past month use of any illicit drug by 8th, 10th, and 12th graders between 2001 and 2005. This trend is driven largely by decreasing rates of marijuana use among these students.