Frequencies for first 10,000 rows of breast variable in nhamcsopd2007 dataset :

breast exam |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,477       94.77       94.77
        yes |        523        5.23      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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