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

   PREVIOUS |
  ACCIDENTS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,797       77.97       77.97
          1 |      1,220       12.20       90.17
          2 |        187        1.87       92.04
          3 |         37        0.37       92.41
          4 |          9        0.09       92.50
          5 |          3        0.03       92.53
         98 |        271        2.71       95.24
         99 |        414        4.14       99.38
          . |         62        0.62      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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