The big US brand has come a long way since it's rescue by Fiat. Lancia inspired fuel-efficient cars have sold well in the US, and now Chrysler is stepping up to the mark in the UK.
Story: John Griffiths
The course is aimed squarely at small businesses to help them with duty of care issues.
The One Day Driver Development Course has been developed in conjunction with the Driving Instructors Association.
It puts drivers into a car with a trained instructor. Fiat says this may be the first time they have been monitored since passing their test.
The predominantly small car maker leads for the second year running.
The average CO2 emissions of Fiat cars are 133.7g/km. Down from 137.3g/km.
Peugeot was second, followed by Citroen, Renault and Toyota.BMW achieved the greatest overall reduction of 16g/km on a year on year basis.
The report was compiled by the consultancy division of JATO Dynamics, a world leader in automotive data provision.