"The number of prisoners sentenced to more than 1 year in federal or state prison, representing 96% of the overall prison population, decreased by 1.7% in 2012 (table 5). The number of sentenced federal prisoners declined slightly (down 0.2%) in 2012, while the total federal population increased. The increase was driven primarily by population increases among inmates without sentences or with sentences of 1 year or less (1,929, not shown in table). The number of sentenced state prisoners also declined, with 25,987 (down 1.9%) fewer sentenced inmates in 2012 than in 2011. California accounted for 57% of this decline. Overall, the number of sentenced male inmates in state or federal prison declined by 1.7% (down 24,109) from 2011 to 2012, and the number of sentenced female inmates decreased by 2.3% (down 2,354) during the same period.
"Among the reporting jurisdictions, 25 out of the 47 states and the federal prison system showed declines in their sentenced prison population (table 6). Five states had decreases of more than 10% in their sentenced female prison population, while five others showed increases among females of more than 10% from 2011 to 2012. However, the majority of these states had a small overall prison population."
Carson, E. Ann, and Golinelli, Daniela. Prisoners in 2012 - Advance Counts. Washington, DC: US Dept. of Justice Bureau of Justice Statistics, July 2013. NCJ242467.