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

     Driver |
   Training |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        830        8.30        8.30
          1 |        103        1.03        9.33
          2 |         37        0.37        9.70
          3 |         16        0.16        9.86
          4 |         31        0.31       10.17
          5 |          4        0.04       10.21
          6 |         12        0.12       10.33
          9 |      8,967       89.67      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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