| Alcohol/drug co-abuse | Number | Percent distribution | ||||||||
| 1992 | 1993 | 1994 | 1995 | 1996 | 1992 | 1993 | 1994 | 1995 | 1996 | |
| Total | 1,479,993 | 1,524,481 | 1,557,892 | 1,556,690 | 1,534,045 | 100.0 | 100.0 | 100.0 | 100.0 | 100.0 |
| Alcohol primary | 857,553 | 846,644 | 807,278 | 764,897 | 757,911 | 57.9 | 55.5 | 51.8 | 49.1 | 49.4 |
| Alcohol only | 535,079 | 511,047 | 472,507 | 440,905 | 432,617 | 36.2 | 33.5 | 30.3 | 28.3 | 28.2 |
| Alcohol w/secondary drug | 322,474 | 335,597 | 334,771 | 323,992 | 325,294 | 21.8 | 22.0 | 21.5 | 20.8 | 21.2 |
| Drug primary | 576,958 | 634,637 | 702,906 | 726,904 | 722,004 | 39.0 | 41.6 | 45.1 | 46.7 | 47.1 |
| Drug only | 304,665 | 334,481 | 375,581 | 389,099 | 382,771 | 20.6 | 21.9 | 24.1 | 25.0 | 25.0 |
| Drug w/secondary alcohol | 272,293 | 300,156 | 327,325 | 337,805 | 339,233 | 18.4 | 19.7 | 21.0 | 21.7 | 22.1 |
| No primary substance reported | 45,482 | 43,200 | 47,708 | 64,889 | 54,130 | 3.1 | 2.8 | 3.1 | 4.2 | 3.5 |
SOURCE: Office of Applied Studies, Substance Abuse and Mental Health Services Administration, TEDS - 1.14.98.