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

  CT Scan - |
 Other than |
       head |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,126       91.26       91.26
        Yes |        874        8.74      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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