"In March 2009, CBP reestablished the Outbound Enforcement Program within its Office of Field Operations. 4 As a result of its outbound enforcement activities, CBP seized about $67 million in illicit bulk cash leaving the country at land ports of entry—97 percent of which was seized along the southwest border— from March 2009 through February 22, 2011. Total seizures account for a small percentage of the estimated $18 billion to $39 billion in illicit proceeds being smuggled across the southwest border annually."

Source

Statement of Richard M. Stana, Director Homeland and Security Issues, Government Accountability Office, before the Senate Caucus on International Narcotics Control, "Moving Illegal Proceeds: Opportunities Exist for Strengthening the Federal Government's Efforts to Stem Cross-Border Currency Smuggling," March 9, 2011, GAO-11-407T, p. 3.
http://www.gao.gov/products/G…