Frequencies for first 10,000 rows of genital variable in natl1998 dataset :

  Malformed |
  genitalia |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          4        0.04        0.04
          2 |      9,980       99.80       99.84
          9 |         16        0.16      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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