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

 compliance |
   with cdl |
endorsement |
          s |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,464       94.64       94.64
          1 |        147        1.47       96.11
          2 |          5        0.05       96.16
          3 |         37        0.37       96.53
          7 |         64        0.64       97.17
          9 |        283        2.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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