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

   PREVIOUS |
  ACCIDENTS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,740       77.40       77.40
          1 |      1,172       11.72       89.12
          2 |        182        1.82       90.94
          3 |         43        0.43       91.37
          4 |          3        0.03       91.40
          5 |          2        0.02       91.42
         98 |        407        4.07       95.49
         99 |        399        3.99       99.48
          . |         52        0.52      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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