ANN ARBOR, MICH (WXYZ) - New vehicles are showing an improved exhaust emission rate.
According to a survey done nationally by the University of Michigan, exhaust emissions for new vehicles is down 14% from 2007.
When comparing the emission rate for April of this year to October of 2007, the results show a drop from 1.0 to 0.86.
University of Michigan Transportation Research Institute Professor Michael Sivak says the significance of the emissions depends on how much fuel is used. He adds the Eco-Driving Index "estimates this amount by taking into account two primary variables-the fuel economy of the vehicle and the distance driven."
The EDI projects the average environmental impact on any given month by someone who bought a new vehicle that month.
The research team figured the monthly EDI by cross-multiplying the average fuel used in the distance driven in a new vehicle. The less impact on the environment was reflected by the lower EDI.
The study also took into account how much driving was done by a particular driver taking into account the different seasons, days of the month and the number of drivers.
In addition to the distance and the weight of the vehicle, EPA fuel ratings and information from monthly sales figures would give the average fuel economy.
For more information about the Eco-Driving Index, go to: www.ecodrivingindex.org