Frequencies for first 10,000 rows of cephalo variable in linkco1991us_num dataset :

Cephalopelv |
         ic |
disproporti |
         on |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        124        1.24        1.24
          2 |      9,656       96.56       97.80
          8 |         13        0.13       97.93
          9 |        207        2.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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