Frequencies for first 10,000 rows of urlgy_srgry_sw variable in pos1998 dataset :

      spec: |
    urology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,416       94.16       94.16
          N |        381        3.81       97.97
          Y |        203        2.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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