Frequencies for first 10,000 rows of catscan variable in nhamcsed2011 dataset :

    CT scan |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      8,453       84.53       84.53
        Yes |      1,547       15.47      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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