Frequencies for first 10,000 rows of prescr4 variable in nhamcsed2007 dataset :

            for rx4, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,345       13.45       13.45
nonprescription drug |        215        2.15       15.60
        undetermined |         30        0.30       15.90
                   . |      8,410       84.10      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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