Millionaires control almost 40% of the world's wealth

That amounts to a cool $47.4 trillion, up from $41.8 trillion in 2009, according to a new report by the consulting firm BCG (via The Wealth Report). The report also notes an increase in the number of millionaire households in the world, to 12.5 million (millionaires are defined as those with $1 million or more in investible assets, excluding homes, luxury goods and ownership in one's own company).

The U.S. continues to lead the world in millionaires, with 5.2 million millionaire households, followed by Japan with 1.5 million millionaire households, China with 1.1 million and the U.K. with 570,000. Singapore leads the world in "millionaire denstiy," or the percentage of millionaires, with 15.5% of its population now millionaire households.