Frequencies for first 10,000 rows of prescr4 variable in namcs2010 dataset :

              prescription status code |      Freq.     Percent        Cum.
---------------------------------------+-----------------------------------
                     prescription drug |      2,168       21.68       21.68
                  nonprescription drug |         77        0.77       22.45
                          undetermined |         35        0.35       22.80
both prescription and over-the-counter |        583        5.83       28.63
                                     . |      7,137       71.37      100.00
---------------------------------------+-----------------------------------
                                 Total |     10,000      100.00

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