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

   PREVIOUS |
  ACCIDENTS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,670       76.70       76.70
          1 |      1,273       12.73       89.43
          2 |        243        2.43       91.86
          3 |         37        0.37       92.23
          4 |          9        0.09       92.32
          6 |          1        0.01       92.33
          7 |          2        0.02       92.35
          8 |          1        0.01       92.36
         98 |        105        1.05       93.41
         99 |        599        5.99       99.40
          . |         60        0.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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