Visualizations : Incarceration Rate (per 100,000 pop.) by U.S. State, Projected 2006 : Have you seen any prosecution data...

“Though the Northeast boasts the lowest incarceration rates, it has the highest costs per prisoner, led by Rhode Island ($44,860), Massachusetts ($43,026) and New York ($42,202). The lowest costs are generally in the South, led by Louisiana ($13,009), Alabama ($13,019) and South Carolina ($13,170).”
The Pew Charitable Trusts’ Public Safety Performance Project Report

The U.S. prison incarceration rate will continue to grow, from 491 per 100,000 U.S. residents in 2005 to 511 in 2006, then to 550 in 2011.
The Pew Charitable Trusts’ Public Safety Performance Project Report

As a sample, statistics for California’s felony and misdemeanor arrests were recently posted. From 2000-2005, felony arrests increased 17% and misdemeanor arrests increased 1.4. Felony arrests for drug offenses increased 24.8 and arrests for dangerous drug offenses increased 60.7%.

Generally, the increased incarceration rate seems to be caused by the 3-Strikes Rule, the war on drugs and probations extending for many years.

The Bureau of Justice statistics on Prisoners in 2005 says Federal prisons were operating at 34% above capacity. State prisons were operating between 1% below and 14% above capacity. This was 3 years ago.