Four out of every five convertible bond traders at banks based in London have lost their jobs during the credit crunch, according to a convertible bond salesman at one bank, as slumping issuance and falling bond values led firms to cut risky activities.

The salesman said about 100 in-house convertible bond traders remain in London, from about 500 before the credit crunch. He said: "The cuts have been harsh. It was a horrible asset class to be in last year."