Frequencies for first 10,000 rows of otherbld variable in nhamcsed1999 dataset :

other blood |
       test |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,850       78.50       78.50
          1 |      2,150       21.50      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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