Frequencies for first 10,000 rows of disch7da variable in nhamcsed2008 dataset :

 discharged |
   from any |
   hospital |
within last |
     7 days |      Freq.     Percent        Cum.
------------+-----------------------------------
      blank |        198        1.98        1.98
    unknown |      3,858       38.58       40.56
        yes |        244        2.44       43.00
         no |      5,700       57.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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