If you binged on sugar last year, you’re probably feeling sick.

Raw sugar futures have fallen for 12 straight weeks, the longest run since data on the contract begins in 1961. While prices are about the same level as a year ago, it’s been a huge swing up and down.

The reasons: a surplus is hitting the market and speculation that India, the world’s top consumer, would need to import the sweetener isn’t materializing.

It’s a lesson in commodity-market volatility. Last year, sugar was the best-performing raw material as forecasts for a deficit lured in speculators and hedge funds. This year, it’s the reverse. Traders are exiting bullish bets and prices are down 17 percent, more than any other crop in the Bloomberg Commodity Index.

“When you see a market inflating like a balloon, then, of course, what’s going up is also going down,” Claudiu Covrig, a senior sugar analyst at Platts Kingsman, said by phone. “I was expecting this low, but how low can we go next?”

Raw sugar for July delivery rose 4.5 percent to settle at 16.13 cents a pound at 1:02 p.m. on ICE Futures U.S. in New York, ending a four-day slump. This week, the price dropped 2.3 percent.

Speculators have been pulling out of the market, and the net-bullish position is down from a record in September, according to data from the U.S. Commodity Futures Trade Commission.

Speculator Swings

“Funds have an important capacity to move the market, and this is what happened in the past two, three years,” Covrig said. “They are looking forward. And forward, we see a year of surplus.”

Output is poised to exceed demand by 3.14 million metric tons in the 2017-2018 season, according to Platts Kingsman. Sugar quotas in the European Union will also end later this year, and producers are getting ready to unleash more supply even as consumption growth slows.

Prospects for extra imports from India are dwindling as Uttar Pradesh expects record output and lower domestic sales, according to Rabobank International.

Technical signals and poor sentiment also contributed to selling by funds this week, according to ADM Investor Services International.

In London, the white-sugar contract rose 2.9 percent to $459.50 a ton. This week, the price has declined 2.5 percent.