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

        MRI |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,905       99.05       99.05
        Yes |         95        0.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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