Frequencies for inj_sev variable in person dataset :

     Injury |
   Severity |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        231       17.47       17.47
          1 |        133       10.06       27.53
          2 |        219       16.57       44.10
          3 |        203       15.36       59.46
          4 |        536       40.54      100.00
------------+-----------------------------------
      Total |      1,322      100.00

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