Frequencies for first 10,000 rows of asthmaed variable in namcs2001 dataset :

     asthma |
  education |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,865       98.65       98.65
          1 |        135        1.35      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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