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

 compliance |
   with cdl |
endorsement |
          s |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,429       94.29       94.29
          1 |        160        1.60       95.89
          2 |          6        0.06       95.95
          3 |         45        0.45       96.40
          7 |         51        0.51       96.91
          9 |        309        3.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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