Currently 8% (19.9 million) of Americans aged 12 or older are current users of illicit drugs. In addition, 6.9 million Americans over the age of 12 were classified as having either abuse of or dependence on illicit substances. This figure has been essentially stable since 2002. Further, it has been estimated that 3% of the US population will meet criteria for dependence on an illicit substance at some point in their lives. The Office of National Drug Control Policy reported that the total cost of drug abuse on society in 2002 was $180.9 billion, and the majority of these costs were crime-related. Other studies have found that the direct effect of drug-related crime (ie, not including the cost of arrest, prosecution, and incarceration) is the largest single cost related to addiction.