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

    Vehicle |
       Role |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        736        7.36        7.36
          1 |      7,095       70.95       78.31
          2 |      1,799       17.99       96.30
          3 |        360        3.60       99.90
          9 |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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