Frequencies for first 10,000 rows of prescr2 variable in nhamcsed2013 dataset :

        Prescription status code for |
                       medication #2 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   Prescription drug |      3,307       33.07       33.07
                Nonprescription drug |         99        0.99       34.06
                        Undetermined |         70        0.70       34.76
Prescription or Nonprescription drug |      1,853       18.53       53.29
                                   . |      4,671       46.71      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016