(Bloomberg News) The commodities rout that knocked off $99 billion of market value last week is driving out speculators and leading Goldman Sachs Group Inc., which forecast the plunge, to predict a possible recovery.

The combination of slower growth in U.S. service industries and fewer German manufacturing orders helped drive the Standard & Poor's GSCI Index of 24 commodities down 11% in five days, the most since December 2008, and erased all the gains since mid-March. Wheat, zinc and gold rebounded at the end of the week as U.S. payrolls exceeded economists' forecasts, reducing concern that demand will weaken.

"Given the magnitude of the pullback, it does create an opportunity for more upside potential, particularly in the second half of this year, when fundamentals are expected to tighten," Jeffrey Currie, the London-based head of commodity research at Goldman, said in a May 6 interview. A month ago, Currie told investors they should be "underweight" in commodities. "In the very near-term, we'd be a little cautious," he says now.

The value of all 24 commodities tracked by the S&P GSCI index was about $805 billion on May 6, compared with $891 billion on April 29, according to data compiled by Bloomberg on the number of outstanding contracts and prices of futures closest to delivery. Combined holdings of exchange-traded products backed by precious metals fell to $119 billion from $132 billion, the data show.

Investment Funds

Speculators retreated after investment funds had made near- record bets on price gains last month and the S&P GSCI reached the highest since August 2008. Commodities beat stocks, bonds and the dollar for five consecutive months through the end of April, the longest in at least 14 years, on forecasts for demand exceeding output in everything from oil to copper to corn.

The most influential analysts and fund managers are divided on where prices are headed. The last time the S&P GSCI fell this much, the index rebounded 12% the following week, and by the end of last month, it had more than doubled.

Bulls say the expanding global economy, led by growth in China, India and Brazil, is boosting demand at a time when producers from BHP Billiton Ltd., the largest mining company, to BP Plc, Europe's second-biggest oil producer, can't keep up.

Selling would be "premature," and the rally will resume, said Hussein Allidina, the head of commodity research at Morgan Stanley in New York, reiterating comments made before the rout. "The decline we are seeing is not being driven by any meaningful change in fundamentals," he said.

'Not Turning Point'