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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        803        8.03        8.03
          1 |      6,018       60.18       68.21
          2 |      2,610       26.10       94.31
          3 |        521        5.21       99.52
          9 |         48        0.48      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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