INSTITUTE INDEX - Locked up by the numbers   U.S. rank among nations with the largest prison populations: 1 Percent of the world's inmates locked up in the U.S. :25 Number of people in U.S. prisons: 2 million Number of people in the U.S. on probation or parole: 5 million Percent of U.S. adults under correctional control: 3.2 Percent of U.S. black adults under correctional control:9.2 Factor by which the U.S. prison population has increased since 1980: 4 Portion of that increase accounted for by the South:almost 1/2 Of the 10 states with the highest incarceration rates, number in the South:7 Amount Louisiana spent on corrections in 2008: $625 million Portion of the state budget that represents: 6.4 percent Percent increase in Louisiana 's incarceration rate since 1982: 272 Portion of adults under correctional supervision in Georgia : 1 in 13 In New Hampshire : 1 in 88 Amount U.S. states spent on corrections in 2008: $68 billion Of every $10 spent on corrections, amount spent on prisons: $9 Increase in U.S. prison costs since 1980: 303 percent Estimated average annual amount spent housing an inmate in the U.S. : $29,000 Estimated average annual cost of managing an offender in the community through probation or parole: $1,250 to $2,750 Percent by which community supervision programs for lower-risk, nonviolent offenders can cut recidivism rates: 30 Amount Texas saved by expanding parole and probation programs: $500 million All sources on file with the Institute for Southern Studies; for more information, e-mail sue@southernstudies .org.