Frequencies for first 10,000 rows of comstat1 variable in namcs2011 dataset :

   Medication #1 - |
Composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |      6,521       65.21       65.21
  Combination drug |      1,248       12.48       77.69
      Undetermined |        161        1.61       79.30
                 . |      2,070       20.70      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016