Frequencies for first 10,000 rows of cbc variable in nhamcsopd2007 dataset :

        cbc |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,017       90.17       90.17
        yes |        983        9.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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