Table 3.3. Clients in treatment, by substance abuse problem and diagnosed co-occurring substance abuse and mental disorders: 2007-20111 Number and percent distribution
Substance abuse problem and diagnosed co-occurring substance abuse and mental disorders	Number of clients					Percent distribution
	2007	2008	2009	2010	2011	2007	2008	2009	2010	2011
Total2	1,135,425	1,192,490	1,182,077	1,175,462	1,224,127	100.0	100.0	100.0	100.0	100.0
Substance abuse problem
Clients with both alcohol and drug abuse	509,919	545,330	517,887	498,671	535,258	44.9	45.7	43.8	42.4	43.7
Clients with drug abuse only	412,400	421,583	441,128	459,069	464,406	36.3	35.4	37.3	39.1	37.9
Clients with alcohol abuse only	211,094	222,389	220,373	215,101	221,632	18.6	18.6	18.6	18.3	18.1
Diagnosed co-occurring substance abuse and mental disorders	416,260	462,260	456,567	479,699	506,162	36.7	38.8	38.6	40.8	41.3
1 Survey reference dates were March 30, 2007, and March 31, 2008-2011. See Appendix A for changes in the survey base, methods, and instruments that affect analysis of trends over time.
2 Totals include clients in facilities that did not respond to the substance abuse problem question (in 2007, 2,011 clients reported by 223 facilities; in 2008, 3,188 clients reported by 188 facilities; in 2009, 2,690 clients reported by 152 facilities; in 2010, 2,620 clients reported by 174 facilities; and in 2011, 2,832 clients reported by 188 facilities)
NOTE: Numbers may not sum to totals and percentages may not sum to 100 percent because of rounding.
SOURCE: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration, National Survey of Substance Abuse Treatment Services (N-SSATS), 2007-2011.