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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,292       12.92       12.92
          1 |      6,058       60.58       73.50
          2 |      1,524       15.24       88.74
          3 |        325        3.25       91.99
          9 |        119        1.19       93.18
          . |        682        6.82      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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