Frequencies for first 10,000 rows of prescr4 variable in nhamcsed2005 dataset :

 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,099       10.99       10.99
nonprescription drug |        212        2.12       13.11
        undetermined |        130        1.30       14.41
                   . |      8,559       85.59      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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