Gold could tumble to a three-month low this week as slowing economic growth erodes demand for raw materials as well as the appeal of precious metals as a hedge against inflation.

The percentage of traders expecting lower prices this week jumped to 41 percent, the highest level since late July, based on a Bloomberg survey of 32 respondents around the world. A week earlier, the percentage was 24 percent.

Twelve said to buy gold this week, and seven were neutral.

Gold has plunged 20 percent from a 26-year high of $732 an ounce on May 12 as two years of interest-rate increases by the Federal Reserve curbed the pace of U.S. economic growth. The Reuters/Jefferies CRB index of 19 commodities posted its biggest three-week decline in more than 25 years.

Gold futures for December delivery fell $34.30, or 5.6 percent, to $583 an ounce last week on the Comex division of the New York Mercantile Exchange.

The CRB index fell 4.2 percent last week to 307.05, after reaching 304.52, its lowest level in more than a year.

The index has fallen 8.7 percent since Aug. 25 and is down 16 percent from a record reached on May 11, snapping a rally that began in October 2001.

Oil prices, which reached a record $78.40 a barrel in July, fell 4.4 percent last week to $63.33 on the New York Mercantile Exchange amid rising U.S. fuel inventories and signs that consumption would ease.

"The weakness in crude is dragging the metal down," said Suresh Hundia of Hundia Exports in Mumbai, India. "Gold is set for further falls."

Gold's value also is being hurt by the reduced risk of inflation. Prices paid by U.S. consumers rose in August at half the pace of the previous month, supporting the view of the Fed chairman, Ben Bernanke, that inflation would moderate.

Some investors buy gold to preserve purchasing power in times of accelerating inflation. Moderation in inflation "should encourage further selling off in the market," said Ralph Preston at Heritage West Financial, a futures brokerage in San Diego.