Consider Manufacturer “A” which produces 5 vehicle models:
Fuel Economy in the United States
August 2008

Vehicle #5 (the SUV) is automatically removed from compliance calculations due to weight exemptions and does not have to abide by current fuel economy standards.

The remaining vehicles (#1, 2, 3 & 4) would be grouped under their respective vehicle categories and compliance calculated as follows:

Fuel Economy Calculation USA

Fuel Economy Compliance Calculation:

Fuel Economy Calculation US
This calculation system allows manufacturers to produce vehicles that do not meet minimum fuel economy standards as long as the average of their differentiated fleets are up to par.