Click here for complete datatable of THC Potency of Tested Cannabis from Federal Seizure and State and Local Eradication Samples, by Type, 1985-2014.

Source

"National Drug Control Strategy Data Supplement 2015," Executive Office of the President, Office of National Drug Control Policy, November 2015, Table 78, p. 92, citing as its sources: University of Mississippi, National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences. Quarterly Report #129, Potency Monitoring Program July 13, 2015) for data from 1995 to 2014; Quarterly Report 107 (January 12, 2010) for data from 1985 to 1994.
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