Frequencies for first 10,000 rows of prescr6 variable in namcs2007 dataset :

 prescription status |
                code |      Freq.     Percent        Cum.
---------------------+-----------------------------------
   prescription drug |      1,131       11.31       11.31
nonprescription drug |        120        1.20       12.51
        undetermined |         37        0.37       12.88
                   . |      8,712       87.12      100.00
---------------------+-----------------------------------
               Total |     10,000      100.00

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