"Colombia is a major source country for cocaine, heroin and marijuana. However, the Government of Colombia continues to make significant progress in its fight against the production and trafficking of illicit drugs. Due to sustained aerial and manual eradication operations and aggressive enforcement activity, potential pure cocaine production declined eight percent, from 190 metric tons (MT) in 2011 to 175 MT in 2012, the most recent year for which figures are available. Although figures are not yet available for 2013, the United States estimated that the area devoted to coca cultivation in 2012 was down an additional six percent compared to 2011, from 83,000 hectares (ha) to 78,000 ha. This represents a 53 percent decline in coca cultivation since 2007.
"According to the U.S. Department of Justice's 2012 Cocaine Signature Program, 95.5 percent of the cocaine in their sampling system seized in the United States originates in Colombia."

Source

United States Department of State Bureau for International Narcotics and Law Enforcement Affairs, "International Narcotics Control Strategy Report: Volume I: Drug and Chemical Control (Washington, DC: March 2014), p. 131.
http://www.state.gov/document…