Frequencies for first 10,000 rows of comstat8 variable in nhamcsopd2011 dataset :

Composition status |
          code for |
     Medication #8 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |        869        8.69        8.69
  Combination drug |         61        0.61        9.30
      Undetermined |         19        0.19        9.49
                 . |      9,051       90.51      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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