Frequencies for first 10,000 rows of contsub1 variable in namcs2013 dataset :

 Controlled substance code |
         for medication #1 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        250        2.50        2.50
              Schedule III |        213        2.13        4.63
               Schedule IV |        179        1.79        6.42
                Schedule V |         18        0.18        6.60
                No control |      6,324       63.24       69.84
              Undetermined |        200        2.00       71.84
        Multiple schedules |         31        0.31       72.15
                         . |      2,785       27.85      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017