Frequencies for first 10,000 rows of otherbld variable in nhamcsed1995 dataset :

other blood |
       test |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,495       74.95       74.95
          1 |      2,505       25.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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