"While the overall illicit drug use rate is holding constant, the number of MRO reviews is increasing (includes legitimate prescription drug use and positive UAs for other pharmaceutical drugs; see Figure 15, page 54). As previously noted, current policy governing prescription drug use may be masking illicit drug use due to open-ended prescriptions. Overall use of amphetamines (including both legal and illegal) is growing at a rate of 2.8 percent per year for all COMPOS. This means that by the end of next year it is expected that there will be over 5,000 MRO [Medical Regulating Officer] reviewable positive tests for amphetamines alone. Among the street drugs, marijuana is increasing significantly within the National Guard population. In fact, if we look at the rate of THC positives over the last four years, it is predicted that over 7,500 Guard Soldiers will test positive for THC this year."

Source

"Army Health Promotion, Risk Reduction and Suicide Prevention Report," United States Army (Washington, DC: 2010), p. 78.
http://www.armyg1.army.mil...