Frequencies for first 10,000 rows of thorc_srgry_sw variable in pos2007 dataset :

      spec: |
   thoracic |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,666       96.66       96.66
          N |        319        3.19       99.85
          Y |         15        0.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017