Frequencies for first 10,000 rows of no_abnorm variable in natl2015 dataset :

No Abnormal |
 Conditions |
  Checked 1 |
       True |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,208       12.08       12.08
          1 |      8,686       86.86       98.94
          9 |        106        1.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Oct 2016