Frequencies for speedrel variable in vehicle dataset :

      SPEED |
    RELATED |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        333       70.55       70.55
          1 |        139       29.45      100.00
------------+-----------------------------------
      Total |        472      100.00

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