Frequencies for first 10,000 rows of otherxry variable in nhamcsed1997 dataset :

other x-ray |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,005       90.05       90.05
          1 |        995        9.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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