Frequencies for first 10,000 rows of comstat9 variable in namcs2013 dataset :

Composition status |
          code for |
     medication #9 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |        909        9.09        9.09
  Combination drug |         71        0.71        9.80
      Undetermined |         17        0.17        9.97
                 . |      9,003       90.03      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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