Demand
There were an estimated 980,000 hardcore heroin addicts in the United States in 1999, 50 percent more than the estimated 630,000 hardcore addicts in 1992. Active occasional users add an estimated 250,000 to 500,000 to the total number of heroin users.
According to reporting from the 1999 NHSDA, an estimated 3.1 million individuals in the United States aged 12 and older had tried heroin in their lifetimes.
The increase in the number of hardcore addicts in the United States likely is attributable to higher heroin purity, lower prices, and ready availability.
December 2001 Drug Threats - Heroin: The demand for heroin in the United States remains high.
http://www.whitehousedrugpolicy.gov/publications/drugfact/american_users_spend/table1.html