Frequencies for first 10,000 rows of contsub5 variable in nhamcsed2011 dataset :

      Controlled substance |
 status code medication #5 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         87        0.87        0.87
              Schedule III |         31        0.31        1.18
               Schedule IV |         24        0.24        1.42
                Schedule V |          1        0.01        1.43
                No control |        764        7.64        9.07
              Undetermined |          7        0.07        9.14
        Multiple schedules |          7        0.07        9.21
                         . |      9,079       90.79      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016