Frequencies for first 10,000 rows of comstat19 variable in namcs2014 dataset :

Composition status |
          code for |
    medication #19 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |         87        0.87        0.87
  Combination drug |         12        0.12        0.99
      Undetermined |          2        0.02        1.01
                 . |      9,899       98.99      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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