Frequencies for first 10,000 rows of prescr3 variable in namcs2009 dataset :

              prescription status code |      Freq.     Percent        Cum.
---------------------------------------+-----------------------------------
                     prescription drug |      3,144       31.44       31.44
                  nonprescription drug |        152        1.52       32.96
                          undetermined |         80        0.80       33.76
both prescription and over-the-counter |        632        6.32       40.08
                                     . |      5,992       59.92      100.00
---------------------------------------+-----------------------------------
                                 Total |     10,000      100.00

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