Frequencies for man_coll variable in vehnit dataset :

  MANNER OF |
  COLLISION |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          2       66.67       66.67
          5 |          1       33.33      100.00
------------+-----------------------------------
      Total |          3      100.00

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