Frequencies for first 10,000 rows of mri variable in nhamcsed1999 dataset :

        mri |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,987       99.87       99.87
          1 |         13        0.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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