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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        858        8.58        8.58
          1 |      6,210       62.10       70.68
          2 |      1,719       17.19       87.87
          3 |        375        3.75       91.62
          9 |          4        0.04       91.66
          . |        834        8.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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