Frequencies for first 10,000 rows of comstat1 variable in namcs2009 dataset :

composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |      6,567       65.67       65.67
  combination drug |      1,236       12.36       78.03
      undetermined |        151        1.51       79.54
                 . |      2,046       20.46      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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