Improving consumer confidence in the U.S. boosted new car sales for Japanese automakers in May, with Toyota Motor Corp. and Nissan Motor Co. posting double digit gains, and Honda Motor Co. rising by 9 percent.

Autodata Corp. also said Tuesday that warmer weather and five full weekends in the month helped attract customers to showrooms and drive sales to levels not seen since before the 2008 recession.

Dealers sold 1.61 million cars and light trucks in May, 11.4 percent more than the year before and the highest monthly sales figure since July 2005, reflecting the stronger U.S. economy.

The total translates into annualized sales of 16.77 million units, staying above the 16 million threshold for the third month in a row and the highest since February 2007, according to the U.S. research company.

Toyota sales rose 17 percent with 243,236 vehicles sold in the month, making it the third-biggest player in the country. The company said increased consumer demand and strong sales of its hybrid Prius line, and its Camry and Corolla sedans contributed to the growth.

"May was just one of those months where everything came together for the industry with five weekends, including an early Memorial Day, one extra selling day, with improved consumer confidence during the month," Toyota group Vice President Bill Fay said Tuesday during a monthly sales call. "(It) resulted in the industry's best volume month in nine years."

Honda sold 152,603 vehicles and the company said its core sedan and sport utility vehicle models drove the robust growth. The automaker expects its new compact car to attract more customers.

Nissan posted a strong 18.8 percent increase, selling 135,934 cars. The Sentra sedan and Rogue SUV set monthly sales records for May while the Leaf electric car passed the 50,000 sales mark in the U.S.