Also, just to add, often times what you are hearing is a prognostication of the range before the sentence is issued. The exception being “25 to life” which is typically only issued in cases that qualify as first degree felonies but happen to have mitigating circumstances heavily factored in.
And, by the way, federal sentences are day-for-day, meaning you do 100% of your time. State sentences are the ones that tend to fluctuate because of “time served” or “good behavior” or “parole.”
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