Frequencies for first 10,000 rows of prescr5 variable in nhamcsed2006 dataset :

             prescr5 |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |        416        4.16        4.16
nonprescription drug |         65        0.65        4.81
        undetermined |         47        0.47        5.28
                   . |      9,472       94.72      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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