Table 3.3 Clients in treatment, by substance abuse problem and diagnosed co-occurring substance abuse and mental health disorders: 2006-2010¹ Number and percent
Substance abuse problem and diagnosed co-occurring substance abuse and mental health disorders	Number of clients					Percent distribution
	2006	2007	2008	2009	2010	2006	2007	2008	2009	2010
Total²	1,130,881	1,135,425	1,192,490	1,182,077	1,175,462
Substance abuse problem
Clients with both alcohol and drug abuse	521,067	509,919	545,330	517,887	498,671	46.1	44.9	45.7	43.8	42.5
Clients with drug abuse only	394,295	412,400	421,583	441,128	459,069	34.9	36.3	35.4	37.3	39.1
Clients with alcohol abuse only	207,194	211,094	222,389	220,373	215,101	18.3	18.6	18.6	18.6	18.3
Diagnosed co-occurring substance abuse and mental health disorders³	n/c	416,260	462,260	456,567	479,699	n/c	36.7	38.8	38.6	40.9
¹Survey reference dates were: March 31, 2006, March 30, 2007, and March 31, 2008-2010. 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 2006, 8,325 clients reported by 278 facilities; 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, and in 2010, 2,620 clients reported by 174 facilities).
³For the diagnosed co-occurring disorders, numbers include clients in facilities that did not respond to the question (in 2007, 17,399 clients reported by 338 facilities; in 2008, 15,462 clients reported by 263 facilities; in 2009, 13,067 clients reported by 220 facilities, and in 2010, 5,593 clients reported by 211 facilities).
^{NOTE: Percentages may not sum to 100 percent because of rounding.}
n/c Not collected until 2007.
SOURCE: Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration, National Survey of Substance Abuse Treatment Services (N-SSATS), 2006-2010.