Frequencies for first 10,000 rows of contsub23 variable in nhamcsed2014 dataset :

      Controlled substance |
status code for medication |
                       #23 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule IV |          3        0.03        0.03
                No control |         10        0.10        0.13
                         . |      9,987       99.87      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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