Frequencies for first 10,000 rows of contsub4 variable in nhamcsopd2011 dataset :

      Controlled substance |
status code for Medication |
                        #4 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         43        0.43        0.43
              Schedule III |         23        0.23        0.66
               Schedule IV |         93        0.93        1.59
                Schedule V |          9        0.09        1.68
                No control |      2,538       25.38       27.06
              Undetermined |         33        0.33       27.39
        Multiple schedules |          5        0.05       27.44
                         . |      7,256       72.56      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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