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

   not_hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        311        3.11        3.11
          1 |        196        1.96        5.07
          2 |        187        1.87        6.94
          3 |        132        1.32        8.26
          4 |        119        1.19        9.45
          5 |        154        1.54       10.99
          6 |        204        2.04       13.03
          7 |        192        1.92       14.95
          8 |        167        1.67       16.62
          9 |        160        1.60       18.22
         10 |        154        1.54       19.76
         11 |        193        1.93       21.69
         12 |        194        1.94       23.63
         13 |        190        1.90       25.53
         14 |        243        2.43       27.96
         15 |        293        2.93       30.89
         16 |        268        2.68       33.57
         17 |        272        2.72       36.29
         18 |        279        2.79       39.08
         19 |        274        2.74       41.82
         20 |        299        2.99       44.81
         21 |        262        2.62       47.43
         22 |        223        2.23       49.66
         23 |        212        2.12       51.78
         24 |          3        0.03       51.81
         99 |      4,819       48.19      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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