"As of the end of fiscal year 2010, there were 191,757 offenders in BOP custody, of whom 111,460 (58.1%) were convicted of an offense carrying a mandatory minimum penalty. Of the 191,757 offenders in BOP custody, 75,579 (39.4%) were subject to that mandatory minimum penalty at sentencing."

Source

"Report to Congress: Mandatory Minimum Penalties in the Federal Criminal Justice System" (Washington, DC: US Sentencing Commission, October 2011), p. 140.
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