Frequencies for first 10,000 rows of injury variable in natl1994 dataset :

     Injury |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          6        0.06        0.06
          2 |      9,938       99.38       99.44
          9 |         56        0.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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