Frequencies for first 10,000 rows of hemo variable in natl1989 dataset :

Hemoglobino |
      pathy |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |      9,797       97.97       97.97
          9 |        203        2.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016