A six-part investigative series by The Center for Public Integrity's International Consortium of Investigative Journalists (ICIJ) details the booming global trade in illegal cigarettes. Since 1999, the ICIJ has tracked the illegal tobacco trade, and found corporate collusion with the criminal networks diverting tobacco shipments to black markets around the world. Crackdowns starting in 2004 have resulted in over $2.75 billion in penalties and pledges by international tobacco companies to help fight trafficking. Despite these efforts "the massive trade in contraband tobacco continues unabated. Indeed, with profits rivaling those of narcotics, and relatively light penalties, the business is fast reinventing itself...The stakes are formidable. Experts estimate that contraband accounts for 11 percent of all cigarette sales, or about 600 billion sticks annually. The cost to governments worldwide is massive: a whopping $40 billion to $50 billion in lost tax revenue during 2006."