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

     Injury |
   Severity |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      2,527       25.27       25.27
          1 |        705        7.05       32.32
          2 |      1,152       11.52       43.84
          3 |      1,175       11.75       55.59
          4 |      4,260       42.60       98.19
          5 |         26        0.26       98.45
          9 |        155        1.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016