Frequencies for first 10,000 rows of prescr3 variable in nhamcsed2015 dataset :

        Prescription status code for |
                       medication #3 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   Prescription drug |      2,498       24.98       24.98
                Nonprescription drug |         77        0.77       25.75
                        Undetermined |         63        0.63       26.38
Prescription or Nonprescription drug |      1,167       11.67       38.05
                                   . |      6,195       61.95      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Nov 2017