OPEN MINDS The Behavioral Health & Social Service Industry Analyst Industry Statistic Chemical dependency admissions to all types of hospitals increased by 27% in the period from 1980 to 1986, according to unpublished data obtained from the National Institute of Mental Health. Hospital admissions for chemical dependency treatment to private psychiatric hospitals and to general hospitals with psychiatric units, increased by 64% and 96%, respectively during the period. Admissions for chemical dependency to state and county mental hospitals decreased by 29%.  By contrast, admissions for mental illness increased only 1.5 . . .