Frequencies for first 10,000 rows of nseiz variable in natl1989 dataset :

   Seizures |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         17        0.17        0.17
          2 |      9,793       97.93       98.10
          9 |        190        1.90      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016