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

 crash time |
     (hour) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        343        3.43        3.43
          1 |        354        3.54        6.97
          2 |        333        3.33       10.30
          3 |        238        2.38       12.68
          4 |        247        2.47       15.15
          5 |        378        3.78       18.93
          6 |        417        4.17       23.10
          7 |        348        3.48       26.58
          8 |        269        2.69       29.27
          9 |        317        3.17       32.44
         10 |        338        3.38       35.82
         11 |        352        3.52       39.34
         12 |        415        4.15       43.49
         13 |        431        4.31       47.80
         14 |        495        4.95       52.75
         15 |        499        4.99       57.74
         16 |        510        5.10       62.84
         17 |        580        5.80       68.64
         18 |        639        6.39       75.03
         19 |        490        4.90       79.93
         20 |        606        6.06       85.99
         21 |        511        5.11       91.10
         22 |        464        4.64       95.74
         23 |        344        3.44       99.18
         99 |         82        0.82      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016