Frequencies for first 10,000 rows of comstat7 variable in nhamcsed2006 dataset :

          for rx7, |
composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |        103        1.03        1.03
  combination drug |         12        0.12        1.15
                 . |      9,885       98.85      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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