Private wealth: Asia-Pacific to overtake Europe in 2014

Private financial wealth around the world increased by 14.6 percent last year to $152.0 trillion helped by rebounding stock markets, with the Asia-Pacific region seeing a 30.5 percent jump, the BCG report said.

That translated into a the number of millionaire households around the world increasing by 2.6 million, to 16.3 million. Close to half were in the United States.

But there was strong growth in private wealth in China, where 2.4 million households count as millionaires, while Japan's number of richest continued to fall.

The BCG study, "Riding a Wave of Growth: Global Wealth 2014", said the largest store of private financial wealth -- cash, securities, and bank deposits but not including real estate or luxury goods -- remains the United States, and Western Europe is second.

But by the end of this year, the Asia-Pacific region excluding Japan will top Europe, which could count $37.9 trillion in private wealth at the end of 2013. And by 2018, Asia will have $61 trillion, more than the $59.1 trillion projected for all of North America and $44.6 trillion for Europe.

"As the debate over the global polarization of wealth rages on, one thing is certain: more people are becoming wealthy," the report said.

The most dense population of millionaires was in Qatar (175 out of every 1,000 households), then Switzerland (127) and Singapore (100).

But Hong Kong had the highest percentage of billionaire households, at 15.3 per million, with Switzerland second.

The shift of wealth from the economic "old world" to the "new world" follows economic growth, and poses new challenges.

"The key challenge in developed economies is how to make the most of a large existing asset base amid volatile growth patterns," said Brent Beardsley, coauthor of the BCG report.