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

    Vehicle |
       Role |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        813        8.13        8.13
          1 |      7,176       71.76       79.89
          2 |      1,675       16.75       96.64
          3 |        325        3.25       99.89
          9 |         11        0.11      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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