Frequencies for first 10,000 rows of prescr3 variable in nhamcsopd2006 dataset :

            for rx3, |
 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   Prescription drug |      2,439       24.39       24.39
Nonprescription drug |        292        2.92       27.31
        Undetermined |        210        2.10       29.41
                   . |      7,059       70.59      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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