Frequencies for first 10,000 rows of chf variable in nhamcsopd2008 dataset :

       does |
patient now |
  have: chf |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,760       97.60       97.60
        yes |        240        2.40      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016