The number may sound unbelievable, but the study was conducted by James Henry, former chief economist at the consultancy McKinsey, an expert on tax havens and offshoring.

FORBES: Super Rich Hide $21 Trillion Offshore, Study Says

But Peter Kongstvedt, a managed-care expert at Ernst and Young, a consultancy, warns that this is far from easy money.

ECONOMIST: American health

But as Jock Encombe, an expert on organisational behaviour at Monitor, a consultancy, points out, there are more and more reasons to take it seriously.

ECONOMIST: Overworked and overpaid: the American manager | The