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

 crash time |
     (hour) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        361        3.61        3.61
          1 |        312        3.12        6.73
          2 |        335        3.35       10.08
          3 |        258        2.58       12.66
          4 |        246        2.46       15.12
          5 |        318        3.18       18.30
          6 |        377        3.77       22.07
          7 |        343        3.43       25.50
          8 |        319        3.19       28.69
          9 |        294        2.94       31.63
         10 |        381        3.81       35.44
         11 |        394        3.94       39.38
         12 |        414        4.14       43.52
         13 |        524        5.24       48.76
         14 |        458        4.58       53.34
         15 |        520        5.20       58.54
         16 |        512        5.12       63.66
         17 |        586        5.86       69.52
         18 |        545        5.45       74.97
         19 |        480        4.80       79.77
         20 |        573        5.73       85.50
         21 |        511        5.11       90.61
         22 |        470        4.70       95.31
         23 |        371        3.71       99.02
         99 |         98        0.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016