It is interesting that the British 50-year bond, though successful, attracted bids equal to only 1.6 times what was on offer, compared with demand equal to three times the total when France launched its ultra-long bond earlier (though different circumstances explain some of that gap).

ECONOMIST: Buttonwood

Developing countries are right that America's offer is unimpressive compared with 1990 figures, but the trajectory from now on is pretty steep.

ECONOMIST: The Copenhagen Summit

Prepaid currency cards are becoming increasingly popular as they offer better exchange rates compared with debit and credit cards.

BBC: Travel money: When is the best time to buy?