Frequencies for first 10,000 rows of retinal variable in namcs2013 dataset :

    Retinal |
       exam |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,702       97.02       97.02
        Yes |        298        2.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017