Frequencies for first 10,000 rows of comstat7 variable in nhamcsed2003 dataset :

composition status |
          code for |
     medication #7 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |        295        2.95        2.95
  combination drug |         35        0.35        3.30
      undetermined |         16        0.16        3.46
                 . |      9,654       96.54      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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