The Chinese currency exchange rate has not been a top concern for U.S. firms in China, Christian Murck, President of the American Chamber of Commerce in the People's Republic of China (AmCham-China), said Monday.

"A singleminded focus on the yuan is a mistake," Murck told reporters at the launch of the commerce chamber's annual report in Beijing.

He said a fluctuation in the yuan's valuation would not have major impact on U.S. firms in China but would reduce the profits of U.S. importers.

Murck said the best way for the U.S. government to bolster its economic growth is to boost its exports, which is more important an issue than pressing China to revalue yuan.

Murck added he will travel to Washington next week to voice the group's position on the matter.

A bigger concern for U.S. firms doing businesses in China is developing opportunities in the fastest-growing market, Murck added.

U.S. firms still considered China among the top destinations for investment and are planning to expand business in China, based upon their optimistic outlook on the Chinese economy, the report said.

The report said 79 percent of respondents planned to increase investment in China in 2010 and more than half of respondents expected their investment growth to be above 10 percent.