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The WardsAuto Fuel Economy Index rating for light vehicles sold in the U.S. fell to 24.7 mpg (9.5 L/100 km) in December, down 0.2% from same-month 2013 and resulting in a second consecutive year-over-year drop as low gasoline prices sway consumers toward less-efficient models.
The national average gasoline price was $2.632 in December, the lowest since October 2009, plummeting 21.6% from the previous year and 12.2% from the prior month. The 2014 annual average was down 3.9% to $3.437. The December LV market share of gas-powered models grew as hybrid and plug-in hybrid models became less popular.
Diesel prices averaged $3.411 in the month, down 12.1% from year-ago. Annually, prices were down 2.5% to $3.825. The share of indexed diesel vehicles rose to 2.5% in December 2014 from 2.3% in the prior year.
The share of cars in the LV market was down every month of 2014 compared with 2013. In December, cars accounted for 44.5% of LV sold in the US and averaged 29.1 mpg (8.1 L/100 km) on the index. Midsize cars was the only car segment to gain market share last month, but it was also the only one to record a lower rating, falling 1.5% to 29.6 mpg (7.9 L/100 km).
Light trucks hit 20.9 mpg (11.3 L/100 km) on the index, up just 0.2% in December. The vehicle-type was up 2.5% for the whole year with a 21.0 mpg (11.2 L/100 km) result. All segments gained market share in the month, but pickups, the lowest-rated group, posted the greatest growth. Vans had a 2.5% improvement from 2013 and a 1.7% increase from November, leading to a record high of 21.3 mpg (11.0 L/100 km).
Mazda regained the top rating (excluding Tesla) after Mitsubishi held the spot for the previous seven months. Mazda’s 29.2 mpg (8.1 L/100 km) December result was 0.6% above same-month 2013. Mazda was one of the most improved automakers over all of 2014, up 8.7% to 29.4 mpg (8 L/100 km). Mitsubishi led all automakers last year, averaging 29.7 mpg (7.9 L/100 km).
BMW’s rating soared 10.9% over the year to 26.2 mpg (8.7 L/100 km), boosted by the introduction of electric and plug-in hybrid models and an increased share of diesel powertrains.
The 12-month average fuel-economy rating for light vehicles sold in 2014 was 25.1 mpg (9.4 L/100 km), 1.6% above 2013.