Frequencies for first 10,000 rows of contsub6 variable in nhamcsopd2011 dataset :

      Controlled substance |
status code for Medication |
                        #6 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         32        0.32        0.32
              Schedule III |          7        0.07        0.39
               Schedule IV |         43        0.43        0.82
                Schedule V |          8        0.08        0.90
                No control |      1,503       15.03       15.93
              Undetermined |         11        0.11       16.04
        Multiple schedules |          2        0.02       16.06
                         . |      8,394       83.94      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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