Frequencies for first 10,000 rows of nochron variable in namcs2007 dataset :

 does patient now |
have: none of the |
   listed chronic |
       conditions |      Freq.     Percent        Cum.
------------------+-----------------------------------
               no |      5,206       52.06       52.06
              yes |      4,554       45.54       97.60
entire item blank |        240        2.40      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

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