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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        820        8.20        8.20
          2 |        700        7.00       15.20
          3 |        740        7.40       22.60
          4 |        838        8.38       30.98
          5 |        803        8.03       39.01
          6 |        738        7.38       46.39
          7 |        869        8.69       55.08
          8 |        928        9.28       64.36
          9 |        874        8.74       73.10
         10 |        988        9.88       82.98
         11 |        874        8.74       91.72
         12 |        828        8.28      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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