Frequencies for first 10,000 rows of catmri variable in namcs1999 dataset :

        cat |
   scan/mri |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,780       97.80       97.80
          1 |        220        2.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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