Frequencies for first 10,000 rows of contsub9 variable in namcs2013 dataset :

 Controlled substance code |
         for medication #9 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         12        0.12        0.12
              Schedule III |         15        0.15        0.27
               Schedule IV |         31        0.31        0.58
                Schedule V |          4        0.04        0.62
                No control |        916        9.16        9.78
              Undetermined |         17        0.17        9.95
        Multiple schedules |          2        0.02        9.97
                         . |      9,003       90.03      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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