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

    VEHICLE |
       ROLE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        676        6.76        6.76
          1 |      6,865       68.65       75.41
          2 |      1,844       18.44       93.85
          3 |        529        5.29       99.14
          9 |         86        0.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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