Frequencies for first 10,000 rows of heart variable in natl1993 dataset :

      Heart |
malformatio |
         ns |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         17        0.17        0.17
          2 |      9,983       99.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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