Frequencies for first 10,000 rows of inj_sev variable in person dataset :

     injury |
   severity |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      2,560       25.60       25.60
          1 |        743        7.43       33.03
          2 |      1,100       11.00       44.03
          3 |      1,167       11.67       55.70
          4 |      4,273       42.73       98.43
          5 |         10        0.10       98.53
          6 |          1        0.01       98.54
          9 |        146        1.46      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016