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

 crash time |
     (hour) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        441        4.41        4.41
          1 |        356        3.56        7.97
          2 |        407        4.07       12.04
          3 |        303        3.03       15.07
          4 |        248        2.48       17.55
          5 |        316        3.16       20.71
          6 |        366        3.66       24.37
          7 |        317        3.17       27.54
          8 |        284        2.84       30.38
          9 |        276        2.76       33.14
         10 |        325        3.25       36.39
         11 |        353        3.53       39.92
         12 |        390        3.90       43.82
         13 |        375        3.75       47.57
         14 |        410        4.10       51.67
         15 |        452        4.52       56.19
         16 |        483        4.83       61.02
         17 |        564        5.64       66.66
         18 |        585        5.85       72.51
         19 |        587        5.87       78.38
         20 |        590        5.90       84.28
         21 |        542        5.42       89.70
         22 |        515        5.15       94.85
         23 |        417        4.17       99.02
         99 |         98        0.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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