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

    TRAFFIC |
   CONTROLS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,985       69.85       69.85
          1 |         77        0.77       70.62
          2 |        115        1.15       71.77
          3 |        747        7.47       79.24
          4 |         24        0.24       79.48
          5 |         14        0.14       79.62
          6 |          3        0.03       79.65
          7 |          6        0.06       79.71
          8 |          5        0.05       79.76
          9 |         15        0.15       79.91
         20 |        815        8.15       88.06
         21 |         13        0.13       88.19
         28 |        786        7.86       96.05
         29 |         34        0.34       96.39
         30 |          2        0.02       96.41
         38 |          2        0.02       96.43
         40 |        203        2.03       98.46
         41 |         11        0.11       98.57
         50 |         17        0.17       98.74
         60 |         15        0.15       98.89
         61 |          5        0.05       98.94
         62 |          1        0.01       98.95
         68 |          2        0.02       98.97
         70 |          9        0.09       99.06
         71 |          2        0.02       99.08
         72 |          2        0.02       99.10
         98 |         10        0.10       99.20
         99 |         80        0.80      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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