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

   PREVIOUS |
  ACCIDENTS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,813       78.13       78.13
          1 |      1,065       10.65       88.78
          2 |        151        1.51       90.29
          3 |         31        0.31       90.60
          4 |         11        0.11       90.71
          5 |          2        0.02       90.73
          6 |          1        0.01       90.74
         98 |        423        4.23       94.97
         99 |        441        4.41       99.38
          . |         62        0.62      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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