Frequencies for first 10,000 rows of comstat5 variable in nhamcsopd2003 dataset :

composition status |
          code for |
     medication #5 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |      1,121       11.21       11.21
  combination drug |        112        1.12       12.33
      undetermined |         30        0.30       12.63
                 . |      8,737       87.37      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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