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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        673        6.73        6.73
          1 |      6,956       69.56       76.29
          2 |      1,878       18.78       95.07
          3 |        461        4.61       99.68
          9 |         32        0.32      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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