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

      Heart |
malformatio |
         ns |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        244        2.44        2.44
          2 |      9,483       94.83       97.27
          9 |        273        2.73      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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