An investor looks at an electronic board showing stock information in Hangzhou, China.

Capital outflows from China topped $500 billion in the first eight months of this year, according to new calculations by the US Treasury that highlight the shifting fortunes in the global economy.

The outflows, which peaked at about $200 billion during the market turmoil in August according to the estimates released on Monday, have also contributed to a shift by Washington in its assessment of the valuation of China's currency, the renminbi.