1992 CENSUS OF TRANSPORTATION
1992 TRUCK INVENTORY AND USE SURVEY


=>COVERAGE

The following types of vehicles were excluded from this survey: those
owned by Federal, State, and local governments, ambulances, buses, and
motor homes. A small number of the vehicles sampled were determined to
be "out-of-scope" of the survey. These cases include but are not limited
to: farm tractors, unpowered trailer units, and trucks reported to have
been sold, junked, or wrecked prior to the registration year.  

Many States allow pickups, small vans, and utility-type vehicles to be
registered as either cars or trucks. The passenger car files were
searched and any such trucks were included in the universe of trucks
from which the sample was selected. Some vehicles such as "off-highway"
trucks used exclusively on private property do not have to be
registered. These vehicles were not included in the universe and had no
chance of being selected.


=>  VEHICLE REGISTRATIONS  

The annual vehicle registration date varies among the States. A few
States use the calendar year for registering all vehicles. Most States
register their vehicle on a staggered basis to permit a distribution of
the renewal workload throughout all months. Most States allow
preregistration or permit "grace periods" to better distribute the
annual registration workload.  

In order to present vehicle registration data uniformly for all States,
the data are shown as nearly as possible on a 1992 calendar-year basis. 

Registration practices for commercial vehicles differ greatly among the
States. Some States register a tractor-semitrailer combination as a
single unit; others register the tractor and the semitrailer separately.
For either, only the power units are included in the registered truck
counts.