Prevalence of Imprisonment in the U.S. Population, 1974-2001

Estimates of the prevalence of ever having gone to prison were derived from generation life table techniques. The prevalence of ever having gone to jail includes adults currently in prison and living former prisoners. One-day counts of adults in prison are available through the National Prisoner Statistics Program (NPS). The NPS has been collecting annually since 1926 and provides a count of persons held in federal and state prisons. To obtain the number of persons who had ever gone to jail, separate generation life tables were prepared for persons alive between 1974 and 2001.

These tables model the first incarceration and mortality experience of each birth cohort as it proceeded through life. Estimates were made of the number of persons going to prison for the first time, by year of age, and the number who had been incarcerated and survived to each later age. Rates of first incarceration during 12 months were developed from prison inmate surveys conducted in 1974, 1979, 1986, 1991, and 1997, during which admission rates increased after many years of relative stability. Prevalence estimates for selected calendar years represent a sum of the contribution of each birth cohort to the total number of adults alive who had ever gone to prison. The number of former prisoners was obtained by subtracting the number of prisoners at yearend (NPS) from the total. Estimates exclude admissions to local jails due to the absence of data to calculate first admissions. (See Methodology for estimation procedures and limitations.)