Total Number of Sentenced People In Federal Prisons, 2004 = 153,776
Total Number of Sentenced People In State Prisons, 2004 = 1,274,600

Total Number of Sentenced People In Federal Prisons In The US For Whom a Drug Charge Was Their Most Serious Offense, 2004: 85,300 (55.5%)
Total Number of Sentenced People In State Prisons In The US For Whom a Drug Charge Was Their Most Serious Offense, 2004: 249,400 (19.6%)

Percent of sentenced people serving time in federal prisons whose most serious drug charges were marijuana/hashish offenses: 2004 = 12.4%
Percent of sentenced people serving time in state prisons whose most serious drug charges were marijuana/hashish, 2004 = 12.7%

(Sentenced people with drug offenses as their most serious charge) * (percent marijuana) = sentenced people serving time for marijuana offenses

Sentenced people serving time in federal prison on marijuana charges, 2004 = 10,577
Sentenced people serving time in state prisons on marijuana charges, 2004 = 31,674
Total sentenced people serving time on marijuana charges, state and federal prisons combined, 2004 = 42,251

Note: These data only address people in prisons and thus exclude everyone serving time in local jails because of a marijuana conviction.

Source

Christopher J. Mumola and Jennifer C. Karberg. Drug Use and Dependence, State and Federal Prisoners, 2004. Bureau of Justice Statistics, US DOJ. January 2007. NCJ 213530.
William J. Sabol, PhD, Heather Couture, and Paige M. Harrison. Prisoners in 2006. Bureau of Justice Statistics, US DOJ. Dec. 2007. NCJ219416.
E. Ann Carson, PhD. Prisoners in 2013. Bureau of Justice Statistics, US DOJ. Sept. 2014. NCJ247282.