Frequencies for first 10,000 rows of blodpres variable in nhamcsopd1992 dataset :

      Blood |
   pressure |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      4,974       49.74       49.74
          1 |      5,026       50.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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