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

    TRAFFIC |
   CONTROLS |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,886       68.86       68.86
          1 |         34        0.34       69.20
          2 |        243        2.43       71.63
          3 |        708        7.08       78.71
          4 |         17        0.17       78.88
          5 |          8        0.08       78.96
          6 |          5        0.05       79.01
          7 |          2        0.02       79.03
          8 |          2        0.02       79.05
          9 |         18        0.18       79.23
         20 |        765        7.65       86.88
         21 |         15        0.15       87.03
         28 |      1,040       10.40       97.43
         29 |          6        0.06       97.49
         39 |          2        0.02       97.51
         40 |        165        1.65       99.16
         41 |         12        0.12       99.28
         50 |         11        0.11       99.39
         60 |          8        0.08       99.47
         61 |          5        0.05       99.52
         62 |          1        0.01       99.53
         63 |          1        0.01       99.54
         68 |          3        0.03       99.57
         69 |          2        0.02       99.59
         70 |          8        0.08       99.67
         71 |          5        0.05       99.72
         72 |          2        0.02       99.74
         80 |          2        0.02       99.76
         98 |          7        0.07       99.83
         99 |         17        0.17      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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