Since taking over last year as chief executive at MF Global, Jon Corzine has pushed the brokerage firm to look much more like Goldman Sachs, where he made his name and fortune as a trader.

Fears that the strategy is a dud deepened Tuesday when MF Global reported a wider fiscal second-quarter loss of $186.6m. The New York company's shares sank $1.69, or 48%, to $1.86, in 4pm New York Stock Exchange composite trading, their second-worst one-day percentage decline ever.