Frequencies for first 10,000 rows of haz_carg variable in vehicle dataset :

  Hazardous |
      Cargo |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,871       98.71       98.71
          1 |         31        0.31       99.02
          9 |         98        0.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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