February marked the second straight month new light vehicles set a U.S.-market record for fuel-efficiency, according to the WardsAuto Fuel-Economy Index.

Cars and light trucks sold in the month had a combined 23.9 mpg (9.8 L/100 km) rating, a 1.5% improvement on the previous benchmark of 23.5 mpg set in prior-month.

The February results also represent a 14.1% increase in fuel efficiency over the index’s base rating of 20.9 mpg (11.2 L/100 km), established in fourth-quarter 2007.

Consecutive records can be viewed as a resumption of the strong upward trend interrupted in March 2011, when the Index hit its previous high-water mark of 23.1 mpg rating.

The Index fell the following month and stayed depressed throughout the summer and fall as sales of small and midsize vehicles suffered after two natural disasters befell Japan – an earthquake and tsunami.

Newly available supplies of these vehicles, combined with soaring gas prices, have focused consumer interest in the more fuel-efficient segments of the market. Small cars accounted for 20.9% of February LV sales, crossing the 20% threshold for the first time since April, while scoring a record 29.4 mpg (8.0 L/100 km) rating.

Midsize vehicles also elevated the average fuel economy, grabbing 22.6% of sales and displacing cross/utility vehicles as the best-selling segment for the first time since August 2009, according to WardsAuto data, while scoring an segment-best 27.2 mpg (8.6 L/100 km) index rating.

Pickup trucks helped the average by accounting for a smaller percentage of sales – just 12.4% of LVs, a nine-month low – while also matching a best-to-date rating of 16.9 mpg (13.9 L/100 km).

Overall, light trucks took 47.6% of February LV sales, the vehicle type’s lowest take in 29 months.

Toyota sat atop the Index, with a record 28.0 mpg (8.4 L/100 km) rating. Hyundai was second at 27.2 mpg (8.6 L/100 km), followed by Kia at 27.0 mpg (8.7 L/100 km) and Volkswagen, which scored its own best-ever 26.8 mpg (8.8 L/100 km) rating in February.

Boosted by an uptick in Focus small-car sales, Ford achieved its best-ever rating – 22.4 mpg (10.5 L/100 km) – to lead all Detroit auto makers.  General Motors and Chrysler scored 21.6 (10.9 L/100 km) and 19.6 (12.0 L/100 km) respectively.

While domestically-built light vehicles averaged an all-time high of 23.0 mpg (10.2 L/100 km), 4.6% over year-ago and a 13.8% jump from the base index rating, the gap between domestic and import LV ratings expanded.

Imported cars and trucks registered a collective 26.9 mpg (8.9 L/100 km), up 6.3% over like-2011 and 16.4% over the base-period rating for the group.

The year-to-date WardsAuto Fuel Economy Index rating for the industry rose to 23.7 mpg (9.94 L/100 km), 4.5% above same-period year-ago.

jsousanis@wardsauto.com