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

    TRAFFIC |
   CONTROLS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,398       73.98       73.98
          1 |         35        0.35       74.33
          2 |         91        0.91       75.24
          3 |        805        8.05       83.29
          4 |         20        0.20       83.49
          5 |         12        0.12       83.61
          7 |          6        0.06       83.67
          8 |          7        0.07       83.74
          9 |         10        0.10       83.84
         20 |        931        9.31       93.15
         21 |         19        0.19       93.34
         28 |        249        2.49       95.83
         29 |          1        0.01       95.84
         30 |          4        0.04       95.88
         38 |          2        0.02       95.90
         39 |          1        0.01       95.91
         40 |        257        2.57       98.48
         50 |         10        0.10       98.58
         60 |         22        0.22       98.80
         61 |         13        0.13       98.93
         62 |          2        0.02       98.95
         70 |         16        0.16       99.11
         71 |          8        0.08       99.19
         72 |          2        0.02       99.21
         98 |          8        0.08       99.29
         99 |         71        0.71      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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