In the continual ebb-and-flow of generally increasing fuel economy for new vehicles purchased, last month American preferences saw the average window sticker value dip 0.1 mpg from September, to a 25.2 mpg average.

The data comes via an ongoing study by the University of Michigan Transportation Research Institute which began Oct. 2007 and now is in its tenth year.

Since the beginning of that study, window sticker averages have increased 5.1 mpg and the numbers are still near their peak – Oct. 2017 was 0.3 mpg below the highest monthly average mpg of 25.5 in Aug. 2014.

These numbers constitute part of the University of Michigan’s Eco-Driving Index (REDI) which measures the amount of greenhouse emissions for every new vehicle, using each vehicle’s fuel economy figures and distance driven as the way to measure. Due to a lag in availability of data, there is a 50 day lag with all new future monthly values.

Leading this study are Michael Sivak and Brandon Schoettle, two researchers from the Transportation Research Institute’s Sustainable Worldwide Transportation research consortium. The consortium’s mission is to advance future transportation issues behind safety and energy, in part by providing technical analysis of future projected trends, using a panel of experts from the University of Michigan and other research organizations. Current members include but are not limited to ExxonMobil, Goodyear Tire, Michelin Americas Research, and Saudi Aramco.

To see the entire EDI summary in .pdf format, click here.

University of Michigan Transportation Research Institute