http://www.usatoday.com/news/nation/2004-11-07-women-prison_x.htm?POE=NEWISVA
Richard Willing
"The population of the nation's state and federal prisons rose to a record 1.47 million last year, the U.S. Bureau of Justice Statistics reported Sunday.
But the rate of growth continues to slow down, suggesting that fewer new inmates are entering prison, but those who are there are serving longer sentences and failing to win early release. The result is a prison population that is more middle-aged than ever.
Nearly 30% of prisoners are age 40 through 54, according to the bureau's annual survey of prisoners. Since 1995, middle-aged prisoners have accounted for nearly half the growth in U.S. prisons."