In the first six months of the year, the average CO2 emissions of new company cars provided by ALD Automotive dropped to an all-time low of 143.9g/km.
That compares with an average of 145.5g/km last year and 166.8g/km in 2003, the year it began recording CO2 emissions data.
The average emission level of company cars supplied by ALD is lower than the national new car CO2 emissions average for the first half of this year of 145.2g/km.
Meanwhile, company cars added to the ALD fleet are also clocking up less mileage.
In the first six months of the year the average annual contracted mileage for company cars was 17,300 miles, down more than 5,000 miles on 2003.
ALD also found that the average contract hire agreement signed in the first six months of this year was for 37.4 months and just over 54,000 miles.
Average new vehicle CO2 emissions and contracted mileage
Year CO2(g/km) Mileage
2010* 143.9 17,301
2009 145.5 18,204
2008 150.5 19,049
2007 155.8 17,198
2006 154.7 19,658
2005 161.4 22,108
2004 167.9 21,592
2003 166.8 22,475
*=Jan to June