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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        782        7.82        7.82
          1 |      5,938       59.38       67.20
          2 |      2,667       26.67       93.87
          3 |        542        5.42       99.29
          9 |         71        0.71      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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