Cocoa futures slumped 10% in New York and London as higher margin calls and uncertainty over a historic crunch has traders pulling out of the market, creating wild price swings.

The most-active contract fell as much as 10% to $9,510 a ton in New York, extending last week’s declines. That’s the biggest intraday drop since 2008. The market has fallen into a correction, with futures dropping about 18% from a record high reached April 19.

The slump comes as the number of outstanding contracts keeps declining, with aggregate open interest nearing the lowest in over a decade, according to data compiled by Bloomberg.

Increases in margin requirements for trading and a large reduction in the number of outstanding contracts “opens up more space for trend reversals, with fewer players being able to drive more abrupt movements,” said StoneX analyst Leonardo Rossetti.

Bean supplies may get some minor relief as rains in West African growing areas could provide some benefit for the region’s upcoming mid-crop harvest. While far from solving a severe shortage that pushed markets to a third year of deficits this season, the wetter weather adds to a lack of new bullish events as money managers continue to trim their net-long positions.

“The shortage is not over,” said consultant Paulo Torres, a London-based trading and agricultural consultant. “The elephant in the room is the fact that Ivory Coast and Ghana do not have cocoa, so there is no way prices can fall significantly.”