Frequencies for first 10,000 rows of weather variable in accident dataset :

Atmospheric |
  Condition |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      9,079       90.79       90.79
          2 |        639        6.39       97.18
          3 |          6        0.06       97.24
          4 |         54        0.54       97.78
          7 |        144        1.44       99.22
          9 |         78        0.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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