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

  if yes, does |
    it include |
       medical |
history/follow |
    -up notes? |      Freq.     Percent        Cum.
---------------+-----------------------------------
         blank |      1,182       11.82       11.82
       unknown |        456        4.56       16.38
not applicable |      4,084       40.84       57.22
           yes |      4,098       40.98       98.20
            no |        180        1.80      100.00
---------------+-----------------------------------
         Total |     10,000      100.00

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