Frequencies for first 10,000 rows of contsub21 variable in nhamcsed2014 dataset :

      Controlled substance |
status code for medication |
                       #21 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |          2        0.02        0.02
                No control |         16        0.16        0.18
              Undetermined |          1        0.01        0.19
                         . |      9,981       99.81      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 11 Apr 2017