Frequencies for first 10,000 rows of catscan variable in nhamcsed1997 dataset :

   cat scan |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,644       96.44       96.44
          1 |        356        3.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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