Frequencies for first 10,000 rows of mri variable in nhamcsopd2007 dataset :

        mri |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,830       98.30       98.30
        yes |        170        1.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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