Frequencies for first 10,000 rows of prescr3 variable in nhamcsed2008 dataset :

   for rx3, prescription status code |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                   prescription drug |      2,278       22.78       22.78
                nonprescription drug |        182        1.82       24.60
                        undetermined |         81        0.81       25.41
prescription or nonprescription drug |        568        5.68       31.09
                                   . |      6,891       68.91      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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