Frequencies for first 10,000 rows of prescr2 variable in nhamcsopd2003 dataset :

 prescription status |
 code for medication |
                  #2 |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      3,116       31.16       31.16
nonprescription drug |        496        4.96       36.12
        undetermined |        281        2.81       38.93
                   . |      6,107       61.07      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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