Frequencies for first 10,000 rows of comstat3 variable in nhamcsed2014 dataset :

Composition status |
          code for |
     medication #3 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |      3,003       30.03       30.03
  Combination drug |        418        4.18       34.21
      Undetermined |         31        0.31       34.52
                 . |      6,548       65.48      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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