Frequencies for first 10,000 rows of catscan variable in nhamcsed2015 dataset :

    CT scan |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      8,334       83.34       83.34
        Yes |      1,666       16.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Nov 2017