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

        cbc |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      6,221       62.21       62.21
        yes |      3,779       37.79      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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