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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        773        7.73        7.73
          2 |        703        7.03       14.76
          3 |        799        7.99       22.75
          4 |        861        8.61       31.36
          5 |        805        8.05       39.41
          6 |        847        8.47       47.88
          7 |        857        8.57       56.45
          8 |        899        8.99       65.44
          9 |        867        8.67       74.11
         10 |        874        8.74       82.85
         11 |        876        8.76       91.61
         12 |        839        8.39      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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