Frequencies for t_cont_f variable in accident dataset :

    Traffic |
    Control |
Device-Func |
    tioning |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        412       84.77       84.77
          1 |          1        0.21       84.98
          3 |         72       14.81       99.79
          9 |          1        0.21      100.00
------------+-----------------------------------
      Total |        486      100.00

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