Frequencies for first 10,000 rows of comstat6 variable in nhamcsopd2006 dataset :

          for rx6, |
composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |        954        9.54        9.54
  Combination drug |        100        1.00       10.54
                 . |      8,946       89.46      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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