Frequencies for first 10,000 rows of breast variable in namcs2005 dataset :

breast exam |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,500       95.00       95.00
          1 |        500        5.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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