Frequencies for first 10,000 rows of prescr6 variable in nhamcsopd2007 dataset :

            for rx6, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,269       12.69       12.69
nonprescription drug |        178        1.78       14.47
        undetermined |         32        0.32       14.79
                   . |      8,521       85.21      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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