The same stocks that had finally attracted greater investor interest for weeks are now experiencing a mass exodus as investors recalibrate their expectations for U.S. economic growth. Amid a turbulent week for stocks, traders pulled $2.6 billion out of the iShares Russell 2000 ETF (ticker symbol IWM) in the five days through Friday, the most in nearly three years, according to data compiled by Bloomberg. And many are betting the worst of the sell-off is yet to come — short interest as a percentage of the fund’s outstanding shares has risen to its highest level since December, according to data from IHS Markit Ltd.

The pullback follows a period in which traders had poured money into previously abandoned strategies that drove the Russell 2000 – the IWM’s underlying index – up 10% in July, its biggest monthly gain since late last year. The index is now down around 8% for August. The drop came as many worry about the health of the U.S. economy and the Federal Reserve’s ability to avoid a recession.

“The trading community is making small caps sour,” Bloomberg Intelligence’s Eric Balchunas said on X. “It was fun while it lasted (about two weeks).”

Investors had been excited about small-cap companies — at least for a few weeks in July — betting that a coming era of lower interest rates and other factors would be beneficial. Previously, the group had been shunned for most of the year in favor of tech giants like Nvidia Corp., which drove the market higher. But the big tech companies took a back seat amid the so-called great rotation, while their smaller counterparts began to gain in earnest.

Then, in recent days, prices have adjusted again after a weaker-than-expected July employment report reignited concerns about the health of the U.S. economy. Markets sold off early last week, with everything from stocks to gold to cryptocurrencies losing value. Although calm returned over the course of the week, the Russell 2000 ended the week down 1.4%, its second consecutive weekly decline.

“One thing is certain: investor concerns have increased in recent weeks,” strategists at Bespoke Investment Group wrote in a statement.

Amid the turmoil, traders also pulled cash from other corners of the market that typically benefit during risk-on periods. The iShares iBoxx High Yield Corporate Bond ETF (HYG) saw an outflow of $1.5 billion last week, while the iShares MSCI Emerging Markets ETF (EEM) saw an outflow of nearly $1.2 billion, the most since October. Meanwhile, large-cap stock indices held up better relative to the small-cap index, with the S&P 500 ending the week little changed.

“While a shift to small caps seems long overdue in the market, recent weakness in labor market indicators has created more uncertainty about the economic outlook and prompted investors to hold on to large caps,” said Roxanna Islam, head of sector and industry research at VettaFi.