Frequencies for first 10,000 rows of f_ob_fail variable in natlterr2008 dataset :

     Failed |
   External |
   Cephalic |
    Version |
(op_ecvf) R |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,066       60.66       60.66
          1 |      3,934       39.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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