Frequencies for first 10,000 rows of disch7da variable in nhamcsed2007 dataset :

 discharged |
   from any |
   hospital |
within last |
     7 days |      Freq.     Percent        Cum.
------------+-----------------------------------
      blank |        223        2.23        2.23
    unknown |      4,278       42.78       45.01
        yes |        247        2.47       47.48
         no |      5,252       52.52      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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