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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        890        8.90        8.90
          1 |      6,173       61.73       70.63
          2 |      1,835       18.35       88.98
          3 |        290        2.90       91.88
          9 |         52        0.52       92.40
          . |        760        7.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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