Frequencies for first 10,000 rows of ab_seiz variable in natlterr2010 dataset :

   Seizures |
        RFP |
633=f_ab_se |
       iz R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,656       46.56       46.56
          N |      4,358       43.58       90.14
          U |        976        9.76       99.90
          Y |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015