Frequencies for first 10,000 rows of prescr5 variable in nhamcsopd2007 dataset :

            for rx5, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,686       16.86       16.86
nonprescription drug |        191        1.91       18.77
        undetermined |         57        0.57       19.34
                   . |      8,066       80.66      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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