Frequencies for first 10,000 rows of otherbld variable in namcs1997 dataset :

other blood |
       test |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,710       87.10       87.10
          1 |      1,290       12.90      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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