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

       hour |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        383        3.83        3.83
          1 |        496        4.96        8.79
          2 |        438        4.38       13.17
          3 |        231        2.31       15.48
          4 |        219        2.19       17.67
          5 |        221        2.21       19.88
          6 |        297        2.97       22.85
          7 |        277        2.77       25.62
          8 |        260        2.60       28.22
          9 |        275        2.75       30.97
         10 |        265        2.65       33.62
         11 |        340        3.40       37.02
         12 |        363        3.63       40.65
         13 |        402        4.02       44.67
         14 |        498        4.98       49.65
         15 |        474        4.74       54.39
         16 |        511        5.11       59.50
         17 |        569        5.69       65.19
         18 |        636        6.36       71.55
         19 |        562        5.62       77.17
         20 |        575        5.75       82.92
         21 |        572        5.72       88.64
         22 |        513        5.13       93.77
         23 |        521        5.21       98.98
         24 |         10        0.10       99.08
         99 |         92        0.92      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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