Frequencies for first 10,000 rows of comstat2 variable in nhamcsed2015 dataset 

Composition status |
          code for |
     medication #2 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |      4,975       49.75       49.75
  Combination drug |        685        6.85       56.60
      Undetermined |         55        0.55       57.15
                 . |      4,285       42.85      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Nov 2017