Frequencies for first 10,000 rows of nochron variable in nhamcsopd2009 dataset :

 does patient now |
have: none of the |
   listed chronic |
       conditions |      Freq.     Percent        Cum.
------------------+-----------------------------------
               no |      5,276       52.76       52.76
              yes |      4,407       44.07       96.83
entire item blank |        317        3.17      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

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