Frequencies for first 10,000 rows of sp_limit variable in accident dataset :

Speed Limit |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         79        0.79        0.79
         10 |          4        0.04        0.83
         15 |         19        0.19        1.02
         20 |         23        0.23        1.25
         25 |        713        7.13        8.38
         30 |        488        4.88       13.26
         35 |      1,332       13.32       26.58
         40 |        659        6.59       33.17
         45 |      1,043       10.43       43.60
         50 |        410        4.10       47.70
         55 |      4,158       41.58       89.28
         99 |      1,072       10.72      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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