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

   not_hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        215        2.15        2.15
          1 |        213        2.13        4.28
          2 |        232        2.32        6.60
          3 |        185        1.85        8.45
          4 |        132        1.32        9.77
          5 |        134        1.34       11.11
          6 |        192        1.92       13.03
          7 |        161        1.61       14.64
          8 |        137        1.37       16.01
          9 |        154        1.54       17.55
         10 |        174        1.74       19.29
         11 |        187        1.87       21.16
         12 |        178        1.78       22.94
         13 |        214        2.14       25.08
         14 |        250        2.50       27.58
         15 |        258        2.58       30.16
         16 |        268        2.68       32.84
         17 |        261        2.61       35.45
         18 |        301        3.01       38.46
         19 |        269        2.69       41.15
         20 |        303        3.03       44.18
         21 |        293        2.93       47.11
         22 |        246        2.46       49.57
         23 |        242        2.42       51.99
         88 |        264        2.64       54.63
         99 |      4,537       45.37      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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