Frequencies for first 10,000 rows of contsub4 variable in nhamcsed2013 dataset :

      Controlled substance |
status code for medication |
                        #4 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        172        1.72        1.72
              Schedule III |         85        0.85        2.57
               Schedule IV |         51        0.51        3.08
                Schedule V |          1        0.01        3.09
                No control |      1,662       16.62       19.71
              Undetermined |         22        0.22       19.93
        Multiple schedules |         10        0.10       20.03
                         . |      7,997       79.97      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016