Frequencies for first 10,000 rows of injury variable in natl1990 dataset :

     Injury |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         15        0.15        0.15
          2 |      9,916       99.16       99.31
          8 |          2        0.02       99.33
          9 |         67        0.67      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015