A consumer reports magazine just published their research on the most fuel-efficient cars sold in America. We are proud to report the BMW i3 Rex claimed the top slot thanks to its eMPG of 139 miles as per Consumer Report’s testing.

To determine scores, the study calculated equal amounts of city and highway driving and rounded the fuel economy numbers from a precision flow meter to the nearest mile per gallon.

The BMW i3 Rex adds a 2-cylinder gasoline engine to the all-electric model which approximately doubles the vehicles driving range. It is not a true hybrid that has two engines collaborating as the Rex in the BMW i3 engages only when the battery is depleted to a certain degree.