Frequencies for first 10,000 rows of contsub2 variable in nhamcsed2011 dataset :

      Controlled substance |
status code for medication |
                        #2 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        471        4.71        4.71
              Schedule III |        202        2.02        6.73
               Schedule IV |        155        1.55        8.28
                Schedule V |         10        0.10        8.38
                No control |      4,246       42.46       50.84
              Undetermined |         60        0.60       51.44
        Multiple schedules |         51        0.51       51.95
                         . |      4,805       48.05      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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