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

   not_hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        244        2.44        2.44
          1 |        174        1.74        4.18
          2 |        180        1.80        5.98
          3 |        130        1.30        7.28
          4 |        125        1.25        8.53
          5 |        146        1.46        9.99
          6 |        161        1.61       11.60
          7 |        159        1.59       13.19
          8 |        111        1.11       14.30
          9 |        126        1.26       15.56
         10 |        146        1.46       17.02
         11 |        150        1.50       18.52
         12 |        165        1.65       20.17
         13 |        172        1.72       21.89
         14 |        225        2.25       24.14
         15 |        231        2.31       26.45
         16 |        210        2.10       28.55
         17 |        237        2.37       30.92
         18 |        268        2.68       33.60
         19 |        250        2.50       36.10
         20 |        243        2.43       38.53
         21 |        242        2.42       40.95
         22 |        220        2.20       43.15
         23 |        217        2.17       45.32
         24 |          3        0.03       45.35
         99 |      5,465       54.65      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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