Frequencies for first 10,000 rows of contsub2 variable in namcs2013 dataset :

 Controlled substance code |
         for medication #2 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        144        1.44        1.44
              Schedule III |         94        0.94        2.38
               Schedule IV |        212        2.12        4.50
                Schedule V |         18        0.18        4.68
                No control |      4,643       46.43       51.11
              Undetermined |        180        1.80       52.91
        Multiple schedules |         20        0.20       53.11
                         . |      4,689       46.89      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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