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

 ton rating |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,178       81.78       81.78
          B |      1,395       13.95       95.73
         BC |          3        0.03       95.76
          C |        263        2.63       98.39
         CD |          2        0.02       98.41
          D |        152        1.52       99.93
         DE |          1        0.01       99.94
         DG |          1        0.01       99.95
          E |          2        0.02       99.97
         FH |          1        0.01       99.98
         GN |          1        0.01       99.99
          P |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016