Frequencies for first 10,000 rows of breast variable in namcs2010 dataset :

breast exam |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,580       95.80       95.80
        yes |        420        4.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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