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

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        397        3.97        3.97
          1 |        405        4.05        8.02
          2 |        406        4.06       12.08
          3 |        246        2.46       14.54
          4 |        248        2.48       17.02
          5 |        293        2.93       19.95
          6 |        326        3.26       23.21
          7 |        353        3.53       26.74
          8 |        282        2.82       29.56
          9 |        264        2.64       32.20
         10 |        295        2.95       35.15
         11 |        378        3.78       38.93
         12 |        365        3.65       42.58
         13 |        430        4.30       46.88
         14 |        454        4.54       51.42
         15 |        524        5.24       56.66
         16 |        542        5.42       62.08
         17 |        532        5.32       67.40
         18 |        518        5.18       72.58
         19 |        534        5.34       77.92
         20 |        564        5.64       83.56
         21 |        562        5.62       89.18
         22 |        484        4.84       94.02
         23 |        437        4.37       98.39
         24 |          8        0.08       98.47
         99 |        153        1.53      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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