"The average sentence length of offenders who remained subject to a mandatory minimum penalty at sentencing was 138 months, over twice the average sentence of offenders receiving relief from such a penalty (66 months). The average sentence for offenders not convicted of any offense carrying a mandatory minimum penalty was 28 months."

Source

US Sentencing Commission, Quick Facts on Mandatory Minimum Penalties, May 2016.
http://www.ussc.gov/research/…
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