Frequencies for first 10,000 rows of contsub4 variable in nhamcsed2011 dataset :

      Controlled substance |
status code for medication |
                        #4 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        156        1.56        1.56
              Schedule III |         68        0.68        2.24
               Schedule IV |         38        0.38        2.62
                Schedule V |          7        0.07        2.69
                No control |      1,341       13.41       16.10
              Undetermined |         18        0.18       16.28
        Multiple schedules |         18        0.18       16.46
                         . |      8,354       83.54      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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