Frequencies for first 10,000 rows of prescr1 variable in nhamcsopd2005 dataset :

 prescription status |
     code for med #1 |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      5,153       51.53       51.53
nonprescription drug |        921        9.21       60.74
        undetermined |        630        6.30       67.04
                   . |      3,296       32.96      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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