Frequencies for first 10,000 rows of retinal variable in namcs2014 dataset :

    Retinal |
       exam |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      8,740       87.40       87.40
        Yes |      1,260       12.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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