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

 crash date |
    (month) |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        891        8.91        8.91
          2 |        785        7.85       16.76
          3 |      1,041       10.41       27.17
          4 |        973        9.73       36.90
          5 |        946        9.46       46.36
          6 |        904        9.04       55.40
          7 |        684        6.84       62.24
          8 |        819        8.19       70.43
          9 |        742        7.42       77.85
         10 |        813        8.13       85.98
         11 |        702        7.02       93.00
         12 |        700        7.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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