Frequencies for first 10,000 rows of comstat8 variable in namcs2007 dataset :

composition status |
              code |      Freq.     Percent        Cum.
-------------------+-----------------------------------
single entity drug |        597        5.97        5.97
  combination drug |         59        0.59        6.56
      undetermined |          2        0.02        6.58
                 . |      9,342       93.42      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

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