Frequencies for first 10,000 rows of prescr4 variable in namcs2009 dataset :

              prescription status code |      Freq.     Percent        Cum.
---------------------------------------+-----------------------------------
                     prescription drug |      2,333       23.33       23.33
                  nonprescription drug |        115        1.15       24.48
                          undetermined |         37        0.37       24.85
both prescription and over-the-counter |        489        4.89       29.74
                                     . |      7,026       70.26      100.00
---------------------------------------+-----------------------------------
                                 Total |     10,000      100.00

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