Frequencies for first 10,000 rows of cardiac variable in natl1997 dataset :

    Cardiac |
    disease |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         58        0.58        0.58
          2 |      9,933       99.33       99.91
          9 |          9        0.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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