Japanese automakers’ U.S. car sales plummeted in August as low gasoline prices instead bolstered their bigger vehicles, mirroring an industry trend.

Toyota’s overall sales declined 5% in August, compared with a year earlier, to 213,125 vehicles, including a 4.6% decline for the namesake Toyota brand and a 7.6% decline for the Lexus luxury brand. Analysts at Edmunds.com and Kelley Blue Book had expected overall Toyota sales declines of 2.7% and 1.1%, respectively.

Nissan’s overall sales fell 6.5% to 124,638 units, including a 6.9% decline for the namesake Nissan brand and a 1.8% decline for the luxury Infiniti brand. Analysts at Edmunds.com and Kelley Blue Book had expected Nissan sales declines of 1.5% and 0.5%, respectively.

And Honda’s sales fell 3.8%, missing expectations of 2.5% growth and 1% growth, respectively. The company’s namesake Honda brand fell 3.5%, while its Acura luxury brand declined 7%.

Across the board, the Japanese automakers’ cars struggled.

Toyota car sales fell 12.5%, Honda car sales declined 11% and Nissan car sales plunged 24.6%.

Nissan’s slump included a stunning 39.2% sales decline for the stalwart Altima sedan, once considered the company’s most important vehicle, to 19,646 units, illustrating the depth of the industry’s shift toward bigger vehicles.

On a positive note, the company’s crossovers, pickup trucks and sport-utility vehicles posted a sales increase of 19%. That included a 19.2% increase for the Rogue compact crossover, which was easily Nissan’s most popular vehicle for the month at 32,979 units.

For the overall industry, compact crossovers gained more than a percentage point in market share to 19.2% in August, compared with a year earlier, according to Kelley Blue Book.

By comparison, midsize cars such as the Altima — once the leading segment in the industry — held only 12.1% market share in August, slipping by more than 2 percentage points.

Automakers boosted incentives by 7.7% in August, compared with a year ago, to $3,331 per vehicle, though that was down 2.2% from July. Analysts are watching closely for signs that the industry is turning to discounts to gain market share.

Follow USA TODAY reporter Nathan Bomey on Twitter @NathanBomey.