Frequencies for first 10,000 rows of impacts variable in vehicle dataset :

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        665        6.65        6.65
          1 |      6,967       69.67       76.32
          2 |      1,804       18.04       94.36
          3 |        503        5.03       99.39
          9 |         61        0.61      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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