Frequencies for first 10,000 rows of comstat18 variable in namcs2014 dataset :

Composition status |
          code for |
    medication #18 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |        116        1.16        1.16
  Combination drug |          5        0.05        1.21
      Undetermined |          3        0.03        1.24
                 . |      9,876       98.76      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017