" While estimating the size of global and hemispheric drug markets presents tremendous challenges, evidence suggests that some two thirds of total revenues are earned at the final, retail level in consuming countries.
" Wholesalers and traffickers through transit countries account for another 20-25 percent of revenues, while just under 1 percent of total retail sales finds its way to drug cultivators in the Andes."
Source
Organization of American States, "The Drug Problem in the Americas: Studies: Chapter 4: The Economics of Drug Trafficking," 2013, p. 5.
http://www.cicad.oas.org/Main…
