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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        807        8.07        8.07
          1 |      5,543       55.43       63.50
          2 |      2,430       24.30       87.80
          3 |        555        5.55       93.35
          9 |         50        0.50       93.85
          . |        615        6.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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