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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        923        9.23        9.23
          1 |      6,256       62.56       71.79
          2 |      1,721       17.21       89.00
          3 |        300        3.00       92.00
          9 |        107        1.07       93.07
          . |        693        6.93      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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