Frequencies for mcarr_id variable in vehicle dataset :

      MOTOR |
 CARRIER ID |      Freq.     Percent        Cum.
------------+-----------------------------------
00000000000 |        490       90.07       90.07
99999999999 |         54        9.93      100.00
------------+-----------------------------------
      Total |        544      100.00

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