China's automobile sales rose 26.9% in November from a year earlier, a Chinese industry group said, but growth is expected to slow sharply next year as the government phases out some incentives and considers measures to curb worsening traffic congestion.

Auto sales in November rose to 1.697 million vehicles, the China Association of Automobile Manufacturers said Thursday, as consumers rushed to take advantage of purchase incentives before they expire at the end of the year. Total industry sales are on track to rise about 32% for the full year to 18 million vehicles, the semi-official association said.

But Xiong Chuanlin, vice secretary of the association, said growth will likely slow to about 10% in 2011, with auto sales totaling approximately 20 million vehicles. That echoes other recent predictions from industry executives.

Joe Hinrichs, head of Asian-Pacific and African operations for Ford Motor Co., said in November that he expects China's overall vehicle sales to total "a little bit shy of 18 million" vehicles this year, and that he expects sales to increase at a much slower rate of about 10% next year. In October, Kevin Wale, head of operations in China for General Motors Co., gave a slightly more conservative estimate, saying he expects auto sales in China to reach 19 million vehicles next year.

China is enormously important to global auto makers, having surpassed the U.S. last year as the world's biggest market by vehicle sales. Much of the growth in the past two years has come from government incentives for purchases of smaller, more fuel-efficient vehicles.

Some of those incentives are now set to expire. China's National Development and Reform Commission said the government will end in 2011 a preferential tax rate of 7.5% for purchases of smaller cars, Chinese state radio reported Thursday. The normal sales tax on cars is 10%. The current rate already represents an increase from a special rate of 5% the government implemented for smaller-car purchases in 2009.

The radio report also said a cash subsidy of 3,000 yuan ($450) a car for purchases of certain fuel-efficient vehicles with engines of 1.6 liters or smaller will expire at the end of this month. That incentive was introduced in June. The report didn't say if that means the commission has ruled out renewing the subsidy. Mr. Xiong of the automobile-manufacturers association said the government is likely extend the 3,000-yuan subsidy.

Expectations that at least some of the incentives might expire have helped passenger-vehicle sales in recent months. Passenger-vehicle sales rose 29.3% in November from a year earlier to 1.34 million vehicles, the association said. The November total was 11.3% higher than October's. Sales of cars with engines 1.6 liters or smaller totaled 939,400 in November, or 70% of total passenger-vehicle sales.

The association said sales have also been driven recently by expectations that Beijing, one of the country's biggest vehicle markets, could issue regulations to limit traffic in the city next year. Chinese media have reported that the capital might start to limit car purchases next year, or take other measures such as raising parking fees, to address the city's notoriously bad traffic jams. But the government hasn't yet announced such measures.