Hedge fund manager Man Group said Wednesday it had lost $6.0 billion (4.4 billion euros) from its asset base since June due to financial markets chaos, sparking a 21-percent plunge in its shares.
Man Group said in a trading update that its total funds under management currently stood at about $65 billion. That compared with $71 billion in June.
In reaction, the group's share price nosedived as much as 21.08 percent to 189.10 pence in morning deals on the London stock market, which was down 0.29 percent.
It stood at 195 pence at about 1000 GMT, down 18.74 percent from Tuesday's close.
"The extreme volatility of markets in recent months has created challenging performance conditions across asset classes," Man Group chief executive Peter Clarke said in the trading statement. "This has tested investor appetite for risk."
In recent weeks and months, global stock markets have tumbled on the back of mounting expectations that the eurozone debt crisis could help spark another fierce worldwide recession.