Be careful what you wish for. For months, City traders had been bemoaning the lack of volatility in most financial markets. Prices were becalmed, making it difficult to find profitable trades and putting a damper on activity by clients. If only there was a bit more volatility, traders cried. Well, in the past few weeks, they certainly got it.

Unfortunately, it was the wrong kind of volatility. The wild swings in equity and bond markets, particularly last week, will have put money in the pockets of those lucky enough to be on the right side. But the violence of the movements may prompt nervous clients to crawl back into their shells.