"For powder cocaine offenders, the most common functions for offenders were High Level Supplier/Importer (24.1%), Courier (21.1%) and Wholesaler (20.7%). The least common functions were Grower/Manufacturer (0.0%), Manager (2.0%) and Supervisor (2.1%).655"

Source

"Report to Congress: Mandatory Minimum Penalties in the Federal Criminal Justice System" (Washington, DC: US Sentencing Commission, October 2011), p. 185.
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