Individual investors were major buyers on Thursday as stocks sold off over concerns that the U.S. Federal Reserve would have to increase the size of interest rate hikes to tame inflation, which is running at a four-decade high.

Retail investors net bought $2.6 billion worth of stocks and exchange traded funds on Thursday, according to Vanda Research. It was the highest level of net buys ever recorded by Vanda, whose data goes back to January 2014, the company said.

Retail investors have become a bigger force in the markets in the past couple of years as online brokerages have dropped trading fees and social media has made it easier for individuals, many working from home due to the pandemic, to coordinate on trading ideas. That can put them at odds with the patterns of institutional investors.

In January 2021, retail investors piled into so-called meme-stocks, like GameStop Corp and AMC Entertainment in an attempt to punish short sellers, but they have largely shifted their attention to tech stocks and index funds.

The top retail purchases during Thursday's selloff, which erased the gains from a relief rally on Wednesday when the Fed raised rates by 0.5%, were: the SPDR S&P 500 ETF Trust, the Invesco QQQ Trust Series 1 ETF, and Apple Inc.

QQQ ETFs track the tech-heavy Nasdaq 100 Index, which is down more than 21% year-to-date. Retail investors were divided on which direction it would head next.

The fourth most popular retail purchase on Thursday was the ProShares UltraPro QQQ ETF, which corresponds to three times (3X) the daily performance of the Nasdaq 100, while the sixth most popular pick was the ProShares UltraPro QQQ Short ETF, which is a 3X bet against the index.

The S&P 500 Index slumped 3.6% on Thursday, and is down around 13% year-to-date.