^* Estimates derived from the implementation of the Office of National Drug Control Policy's Sequential Transition and Reduction (STAR) Model, December 1999.

¹ Estimates of cocaine hydrochloride come from a computer model of cocaine production. The range is based on the error band reported by the Department of State for the area under cultivation.

² Estimates are a two-year moving average of years T and T-1. The estimate for 1989 is for year 1989 alone.

Source: 1989 to 1998 data from Office of National Drug Control Policy. 1999. What America's Users Spend on Illegal Drugs, 1988–1998. Cocaine HCI data for 1996 to 1998 are from ONDCP's Sequential Transition and Reduction (STAR) Model, December 1999.