Americans may benefit from some of the lowest new car prices in the world but the average motorist in the U.S. is keeping their cars for longer a new study has found. According to the results the median age of cars on U.S. roads was 9.2 years in 2007, a new record, and a substantial 41.3% of call vehicles were 11 years or older compared to just 40.9% the year before.

The study, conducting by automotive consulting firm R.L. Polk & Co., concluded that improvements in vehicle quality and uncertainty about the economy were the main factors for the increase. The study also reflects a drop in sales of new cars last year, falling 3% on the year before, mainly because of including high fuel prices and the housing crisis.

Dave Goebel, from R.L. Polk, told reporters from MSNBC the increasing durability, not the economy, is the main driver of rising vehicle age. There are more vehicles per household than in the past, he said, indicating that people buy cars and then hang on to them because they last longer."Each new model year the technology continues to get better and there are fewer components that fail, so we expect to see these trends continue," he said.

The Polk report was based on a survey of 240.9 million cars and light trucks.