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

   PREVIOUS |
   SPEEDING |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,815       78.15       78.15
          1 |      1,266       12.66       90.81
          2 |        321        3.21       94.02
          3 |         92        0.92       94.94
          4 |         34        0.34       95.28
          5 |         13        0.13       95.41
          6 |          3        0.03       95.44
          7 |          4        0.04       95.48
         11 |          1        0.01       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