Frequencies for first 10,000 rows of comstat4 variable in namcs2008 dataset :

composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |      2,501       25.01       25.01
  combination drug |        315        3.15       28.16
                 . |      7,184       71.84      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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