Frequencies for first 10,000 rows of cleftlp variable in natl1992 dataset :

      Cleft |
 lip/palate |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          2        0.02        0.02
          2 |      9,995       99.95       99.97
          9 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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