Frequencies for first 10,000 rows of prescr8 variable in namcs2007 dataset :

 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |        576        5.76        5.76
nonprescription drug |         66        0.66        6.42
        undetermined |         16        0.16        6.58
                   . |      9,342       93.42      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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