Frequencies for veh_cf1 variable in vehicle dataset :

    RELATED |
   FACTOR 1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        671       93.72       93.72
          1 |          1        0.14       93.85
          2 |          1        0.14       93.99
         18 |          4        0.56       94.55
         31 |         39        5.45      100.00
------------+-----------------------------------
      Total |        716      100.00

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