Frequencies for first 10,000 rows of prescr1 variable in nhamcsed2007 dataset :

            for rx1, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      6,107       61.07       61.07
nonprescription drug |      1,538       15.38       76.45
        undetermined |        121        1.21       77.66
                   . |      2,234       22.34      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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