Persons between ages 35 and 44 accounted for the largest number of current and former prisoners at yearend 2001 (table 2). Born between 1957 and 1966, these persons turned 18 in the late 1970s and early 1980s when first incarceration rates began to climb. Between 1974 and 2001, the number ever incarcerated in this age group rose from 324,000 to 1.67 million.

Among persons between ages 25 and 34, the number ever incarcerated nearly quadrupled (from 343,000 in 1974 to 1.29 million in 2001). While persons in this age group also experienced rising first incarceration rates, they were subject to these rates for a smaller portion of their lifespan than those ages 35 to 44.

As a percent of those ever incarcerated, persons ages 35 to 44 increased from 18% in 1974 to 30% by 2001; persons age 25 to 34 increased from 19% in 1974 to 23% in 2001.

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Table 1. Prevalence of incarceration in a State or Federal prison, by
current and former prisoners, 1974-2001
Current and former prisoners ever incarcerated in a State
or Federal prison--
1974 1979 1986 1991 1997 2001
Number incarcerated
Total 1,819,000 2,100,000 2,667,000 3,437,000 4,652,000 5,618,000
Current 216,000 302,000 524,000 788,000 1,171,000 1,319,000
Former 1,603,000 1,798,000 2,143,000 2,649,000 3,481,000 4,299,000
Ever incarcerated rate*
Total 1,251 1,308 1,516 1,828 2,336 2,673
Current 149 188 298 419 588 628
Former 1,102 1,120 1,218 1,409 1,748 2,045
Note: Numbers of current adult prisoners from National Prisoner Statistics
data series. Former prisoner statistics based on inmate survey data.
Estimates were rounded to the nearest 1,000. See Methodology for
estimation procedures.
*The number ever incarcerated per 100,000 adult U.S. residents.
U.S. adult resident population
1974 1986 1991 1997 2001
145,356,000 175,886,630 187,982,751 199,121,734 210,207,901
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Prevalence rates up sharply among persons under age 50

Between 1974 and 2001, the rise in first incarceration rates had the largest effects on younger age groups. The percent of persons ever incarcerated tripled among persons ages 25 to 29 (from 1.0% in 1974 to 3.1% in 2001)and more than doubled among persons ages 30 to 34 (from 1.3% to 3.7%) and persons ages 35 to 39 (from 1.4% to 3.8%) (table 3).

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Table 3. Percent of adult population ever incarcerated in a State or
Federal prison, by age, 1974-2001
Percent of adult population ever incarcerated in a State
or Federal prison
Age 1974 1979 1986 1991 1997 2001
Total 1.3% 1.3% 1.5% 1.8% 2.3% 2.7%
18-19 0.3 0.3 0.4 0.5 0.6 0.6
20-24 0.7 0.8 1.0 1.3 1.8 1.8
25-29 1.0 1.2 1.6 2.1 2.7 3.1
30-34 1.3 1.3 1.8 2.3 3.2 3.7
35-39 1.4 1.4 1.7 2.3 3.1 3.8
40-44 1.5 1.5 1.7 2.1 2.9 3.6
45-49 1.5 1.5 1.7 1.9 2.5 3.2
50-54 1.5 1.5 1.7 1.8 2.2 2.6
55-59 1.5 1.6 1.6 1.8 2.0 2.2
60-64 1.5 1.5 1.6 1.6 1.9 2.0
65 or older 1.5 1.5 1.5 1.6 1.6 1.7
Note: Percents by age were based on intercensal resident population
estimates from the U.S. Census Bureau. See Methodology for data
sources.
U.S. adult resident population
1974 1979 1986 1991 1997 2001
Total 145,356,000 160,463,000 175,886,630 187,982,751 199,121,734 210,207,901
18-19 8,196,000 8,698,000 7,571,080 7,562,252 7,629,647 8,349,428
20-24 18,757,000 21,096,000 21,147,811 19,756,380 18,078,783 19,863,153
25-29 16,429,000 19,078,000 21,742,173 21,509,229 19,529,293 18,057,849
30-34 13,644,000 16,960,000 20,167,953 22,482,213 21,434,194 19,971,052
35-39 11,400,000 13,591,000 17,839,473 20,486,038 22,851,041 21,801,103
40-44 11,355,000 11,522,000 14,185,094 18,553,907 21,376,552 23,144,035
45-49 11,843,000 11,211,000 11,658,854 14,135,160 18,558,879 20,879,652
50-54 11,958,000 11,725,000 10,868,729 11,410,881 14,518,458 18,117,187
55-59 10,386,000 11,582,000 11,210,396 10,345,736 11,434,732 14,092,339
60-64 9,327,000 9,867,000 10,902,949 10,518,068 9,913,280 11,049,281
65 or older 22,061,000 25,133,000 28,592,118 31,222,887 33,796,875 34,882,826
Note: Because of estimation and other rounding procedures, some detail may
not add to totals and may not match precisely totals in other tables.
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In contrast, the rise in the percents ever incarcerated was more modest among persons 50 or older. Although these age groups also experienced rising first incarceration rates, they were exposed at older ages when first incarceration rates are low. Persons age 65 and older were the least affected by the increases in first incarceration rates, with percents ever incarcerated rising from 1.5% in 1974 to 1.7% in 2001.

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Table 4. Number of adults ever incarcerated in a State or Federal
prison, by gender, race, and Hispanic origin, 1974-2001
Number of adults ever incarcerated in a State or Federal prison
1974 1979 1986 1991 1997 2001
Gender
Male 1,677,000 1,934,000 2,449,000 3,142,000 4,205,000 5,037,000
Female 142,000 165,000 217,000 295,000 447,000 581,000
Race/Hispanic origin
White* 922,000 1,052,000 1,286,000 1,533,000 1,909,000 2,203,000
Male 837,000 958,000 1,173,000 1,395,000 1,724,000 1,978,000
Female 86,000 94,000 113,000 139,000 185,000 225,000
Black* 646,000 766,000 963,000 1,290,000 1,784,000 2,166,000
Male 595,000 704,000 881,000 1,181,000 1,615,000 1,936,000
Female 51,000 62,000 82,000 109,000 170,000 231,000
Hispanic 102,000 125,000 234,000 422,000 721,000 997,000
Male 94,000 116,000 217,000 392,000 664,000 911,000
Female 8,000 10,000 17,000 30,000 57,000 86,000
Note: Estimates were based on separate generation life tables that
incorporate first incarceration and mortality rates for each age
group. Estimates were rounded to the nearest 1,000. See Methodology for estimation procedures.
*Excludes persons of Hispanic origin.
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These changes in the percents ever incarcerated by age reflect rising rates of first incarceration and the age of each of these birth cohorts when the increases occurred. In the future, the percents ever incarcerated will rise among older age groups as more recent cohorts experience the full impact of current levels of first incarceration rates throughout their lifetimes (figure 2).