Frequencies for first 10,000 rows of prov2010 variable in pos1993 dataset :

        630 |
   cytology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,797       87.97       87.97
          N |        888        8.88       96.85
          Y |        315        3.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016