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

      Fetal |
   distress |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        479        4.79        4.79
          2 |      9,295       92.95       97.74
          8 |          1        0.01       97.75
          9 |        225        2.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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