Frequencies for first 10,000 rows of prescr7 variable in nhamcsopd2006 dataset :

            for rx7, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   Prescription drug |        593        5.93        5.93
Nonprescription drug |        118        1.18        7.11
        Undetermined |         66        0.66        7.77
                   . |      9,223       92.23      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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