Frequencies for first 10,000 rows of uld_cephal variable in natlterr2003 dataset :

Cephalopelv |
         ic |
Disproporti |
       on U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        696        6.96        6.96
          2 |      9,278       92.78       99.74
          8 |         23        0.23       99.97
          9 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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