Frequencies for first 10,000 rows of contsub8 variable in nhamcsopd2011 dataset :

      Controlled substance |
status code for Medication |
                        #8 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         20        0.20        0.20
              Schedule III |         10        0.10        0.30
               Schedule IV |         28        0.28        0.58
                Schedule V |          4        0.04        0.62
                No control |        868        8.68        9.30
              Undetermined |         19        0.19        9.49
                         . |      9,051       90.51      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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