Frequencies for month variable in vehicle dataset :

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         37        6.80        6.80
          2 |         49        9.01       15.81
          3 |         34        6.25       22.06
          4 |         37        6.80       28.86
          5 |         43        7.90       36.76
          6 |         42        7.72       44.49
          7 |         58       10.66       55.15
          8 |         54        9.93       65.07
          9 |         32        5.88       70.96
         10 |         42        7.72       78.68
         11 |         61       11.21       89.89
         12 |         55       10.11      100.00
------------+-----------------------------------
      Total |        544      100.00

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