| Alcohol/Drug Co-Abuse | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Drug Only | 24.6 | 25.7 | 26.4 | 27.4 | 29.6 | 31.1 | 31.8 | 33.7 | 35.2 | 36.6 | 37.0 |
| Drug with Secondary Alcohol | 22.3 | 22.4 | 22.3 | 22.1 | 21.6 | 21.9 | 21.9 | 21.9 | 21.8 | 21.6 | 21.0 |
| Alcohol Only | 28.8 | 27.7 | 27.0 | 26.7 | 25.8 | 24.4 | 23.6 | 23.1 | 22.1 | 21.7 | 21.9 |
| Alcohol with Secondary Drug | 21.9 | 21.8 | 21.3 | 21.0 | 20.4 | 19.9 | 19.2 | 18.5 | 17.8 | 17.6 | 17.8 |
| No Substance Reported | 2.5 | 2.4 | 2.9 | 2.7 | 2.6 | 2.7 | 3.4 | 2.9 | 3.1 | 2.5 | 2.4 |