Frequencies for first 10,000 rows of distress variable in natl1999 dataset :

      Fetal |
   distress |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        351        3.51        3.51
          2 |      9,647       96.47       99.98
          8 |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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