Frequencies for first_mo variable in vehicle dataset :

      FIRST |
ACCIDENT-MO |
        NTH |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        539       70.55       70.55
          1 |         21        2.75       73.30
          2 |         19        2.49       75.79
          3 |         19        2.49       78.27
          4 |         11        1.44       79.71
          5 |         15        1.96       81.68
          6 |         17        2.23       83.90
          7 |         12        1.57       85.47
          8 |         14        1.83       87.30
          9 |         18        2.36       89.66
         10 |         13        1.70       91.36
         11 |          6        0.79       92.15
         12 |          5        0.65       92.80
         99 |         53        6.94       99.74
          . |          2        0.26      100.00
------------+-----------------------------------
      Total |        764      100.00

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