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

   previous |
   recorded |
    crashes |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,752       77.52       77.52
          1 |      1,012       10.12       87.64
          2 |        200        2.00       89.64
          3 |         53        0.53       90.17
          4 |          8        0.08       90.25
          5 |          2        0.02       90.27
          6 |          1        0.01       90.28
          7 |          2        0.02       90.30
         98 |        436        4.36       94.66
         99 |        483        4.83       99.49
        998 |         51        0.51      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016