Japan's richest have the largest accumulation of wealth in the Asia-Pacific region, at $7.7 trillion, but the legions of Chinese millionaires are rushing to catch up.

The pool of wealth held by China's high net worth individuals grew by more than 144 percent between 2010 and 2017, to reach $6.5 trillion, according to the latest Asia-Pacific Wealth Report from consultants Capgemini. The equivalent rate of growth in Japan over the same period was about 87 percent.

The firm defines high net worth individuals as those with investable assets of more than $1 million.