The report finds that public payers began to bear a growing share of spending for mental health and substance abuse treatment.   

From the report: 

This paper addresses the following key questions: (1) How much was spent in the United States to provide M/SU treatment in 2001? (2) How were the expenditures for M/SU distributed by payer and provider type? (3) How did spending change from 1991 to 2001? (4) How did M/SU spending compare with spending for all U.S. health care?

Full report: Trends: U.S. Spending for Mental Health and Substance Abuse Treatment, 1991-2001 the Decline in Receipt of Substance Abuse Treatment by the Privately Insured, 1992-2001 (PDF | 117.67 KB) 

U.S. Dept. of Health and Human Services. Substance Abuse and Mental Health Services Administration (SAMHSA). (2005). Trends: U.S. Spending for Mental Health and Substance Abuse Treatment, 1991-2001 the Decline in Receipt of Substance Abuse Treatment by the Privately Insured, 1992-2001. Mark, T.L., Coffey, R.M., Vandivort-Warren, R., Harwood, H.J., King, E.C. and the MHSA Spending Estimates Team.