Defrosted from his cryogenic state Dr Evil in the comedy film Austin Powers discovered, “one million dollars” is less impressive than it used to be. A survey by Boston Consulting Group suggests there are no less than 7.2m dollar-millionaire households globally. Together, they own $25,000bn of financial assets – excluding unquoted businesses, residences and luxury goods – or 29 per cent of the world’s total.

At the mega-rich level, the evolution of the world economy is already being felt. Forbes magazine estimates that 12 of the world’s 45 wealthiest individuals or families are from emerging economies, led by Carlos Slim and Lakshmi Mittal. Overall, however, the developed world still owns 85 per cent of total financial assets. The total weight of Brazil, Russia, India and China is only 5 per cent, half their share of output at market prices. China’s 250,000 millionaires merely put it on a par with Philadelphia and Detroit combined. India has only 10,000 households with six-figure wealth.