Frequencies for first 10,000 rows of prescr4 variable in nhamcsopd2003 dataset :

 prescription status |
 code for medication |
                  #4 |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,442       14.42       14.42
nonprescription drug |        202        2.02       16.44
        undetermined |        127        1.27       17.71
                   . |      8,229       82.29      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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