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

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        375        3.75        3.75
          1 |        400        4.00        7.75
          2 |        413        4.13       11.88
          3 |        271        2.71       14.59
          4 |        251        2.51       17.10
          5 |        277        2.77       19.87
          6 |        344        3.44       23.31
          7 |        321        3.21       26.52
          8 |        280        2.80       29.32
          9 |        281        2.81       32.13
         10 |        302        3.02       35.15
         11 |        339        3.39       38.54
         12 |        398        3.98       42.52
         13 |        407        4.07       46.59
         14 |        498        4.98       51.57
         15 |        522        5.22       56.79
         16 |        524        5.24       62.03
         17 |        561        5.61       67.64
         18 |        566        5.66       73.30
         19 |        533        5.33       78.63
         20 |        549        5.49       84.12
         21 |        564        5.64       89.76
         22 |        474        4.74       94.50
         23 |        417        4.17       98.67
         24 |          7        0.07       98.74
         99 |        126        1.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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