Greek travel agents are complaining that - despite the attraction of the Olympic Games in Athens this August - hotel bookings are down 10%-plus over last year's.

There are a lot of excuses - hoteliers raising prices to cash in on the Games, travellers' uncertainties about whether Games venues will be finished, continuing security concerns...

But to me the most obvious reason is that Greece is just 10%-plus more expensive than last year, because it is now in the Euro area.

One monetary size just cannot fit all, and I fear that Greece is suffering. The Business newspaper reports that Milton Friedman, the veteran free-market Nobel economist, believes the Euro may collapse under the strain of having to cope with ten new member states. "Differences are already accumulating between countries. The euro zone could collapse... It is a strong possibility." Already the euro zone is lagging, with expected growth of 1.6% this year, as against 4.7% for the US. According to David Smith, UK economist at Williams de Broe, the euro zone's high regulation and taxation puts it "in the geriatric ward of the world economy."