Frequencies for first 10,000 rows of comstat1 variable in namcs2010 dataset :

composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |      6,494       64.94       64.94
  combination drug |      1,282       12.82       77.76
      undetermined |        154        1.54       79.30
                 . |      2,070       20.70      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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