Frequencies for first 10,000 rows of comstat7 variable in nhamcsopd2006 dataset :

          for rx7, |
composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |        702        7.02        7.02
  Combination drug |         75        0.75        7.77
                 . |      9,223       92.23      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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