Frequencies for first 10,000 rows of comstat5 variable in nhamcsed2004 dataset :

composition status |
          code for |
     medication #5 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |        888        8.88        8.88
  combination drug |        160        1.60       10.48
      undetermined |         36        0.36       10.84
                 . |      8,916       89.16      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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