Frequencies for first 10,000 rows of nochron variable in namcs2012 dataset :

 Does patient now |
have: None of the |
            above |      Freq.     Percent        Cum.
------------------+-----------------------------------
               No |      5,140       51.40       51.40
              Yes |      4,500       45.00       96.40
Entire item blank |        360        3.60      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

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