Frequencies for first 10,000 rows of outcome variable in natl1983 dataset :

 Outcome of |
       Last |
  Pregnancy |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      3,757       37.57       37.57
          1 |      5,032       50.32       87.89
          2 |      1,119       11.19       99.08
          3 |         92        0.92      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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