Frequencies for emer_use variable in vehnit dataset :

  EMERGENCY |
        USE |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,389       99.71       99.71
          1 |          4        0.29      100.00
------------+-----------------------------------
      Total |      1,393      100.00

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