Frequencies for first 10,000 rows of prescr6 variable in nhamcsed2010 dataset :

            Prescription status code |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   prescription drug |        444        4.44        4.44
                nonprescription drug |         11        0.11        4.55
                        undetermined |          4        0.04        4.59
prescription or nonprescription drug |        115        1.15        5.74
                                   . |      9,426       94.26      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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