Frequencies for first 10,000 rows of blodpres variable in namcs2010 dataset :

      blood |
   pressure |
      taken |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      3,330       33.30       33.30
        yes |      6,670       66.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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