Frequencies for first 10,000 rows of comstat6 variable in namcs2013 dataset :

Composition status |
          code for |
     medication #6 |      Freq.     Percent        Cum.
-------------------+-----------------------------------
Single entity drug |      1,705       17.05       17.05
  Combination drug |        173        1.73       18.78
      Undetermined |         57        0.57       19.35
                 . |      8,065       80.65      100.00
-------------------+-----------------------------------
             Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017