Frequencies for first 10,000 rows of prescr2 variable in namcs2011 dataset :

   Medication #2 - Prescription status |
                                  code |      Freq.     Percent        Cum.
---------------------------------------+-----------------------------------
                     Prescription drug |      4,313       43.13       43.13
                  Nonprescription drug |        136        1.36       44.49
                          Undetermined |         99        0.99       45.48
Both Prescription and Over-The-Counter |      1,042       10.42       55.90
                                     . |      4,410       44.10      100.00
---------------------------------------+-----------------------------------
                                 Total |     10,000      100.00

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