Frequencies for first 10,000 rows of prescr4 variable in namcs2008 dataset :

              prescription status code |      Freq.     Percent        Cum.
---------------------------------------+-----------------------------------
                     prescription drug |      2,238       22.38       22.38
                  nonprescription drug |        108        1.08       23.46
                          undetermined |         54        0.54       24.00
both prescription and over-the-counter |        416        4.16       28.16
                                     . |      7,184       71.84      100.00
---------------------------------------+-----------------------------------
                                 Total |     10,000      100.00

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