Frequencies for first 10,000 rows of urlgy_srgry_sw variable in pos1992 dataset :

      spec: |
    urology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,640       96.40       96.40
          N |        216        2.16       98.56
          Y |        144        1.44      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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