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

      spec: |
    urology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,666       96.66       96.66
          N |        220        2.20       98.86
          Y |        114        1.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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