Billionaire investor Ken Griffin’s hedge funds crushed the market in January as a spike in volatility and a steep sell-off in growth stocks created an ideal environment for fast-money traders.

Citadel’s multistrategy flagship fund Wellington gained 4.71% last month, according to a person familiar with the returns.

Citadel’s global fixed income fund did even better with a 4.91% return, while its equities fund gained 0.89% and its tactical trading strategy rose 1.79% last month, according to the source.

The firm’s stellar performance came when wild price swings gripped Wall Street with the Federal Reserve’s hawkish policy pivot in focus. The S&P 500 dropped more than 5% for its worst month since March 2020, while the tech-heavy Nasdaq Composite dipped into correction territory, or falling more than 10% from its record high.

In fact, the hedge fund industry as a whole fared well in the volatile January. All major hedge fund categories outperformed the overall market last month with funds least correlated with the market delivering the strongest returns, according to data from Bank of America.

At the beginning of 2022, surging bond yields triggered hedge funds to sell growth-focused technology shares at a speed not seen in the past decade, according to Goldman Sachs’ prime brokerage data.

Tech stocks are seen as sensitive to rising yields because increased debt costs can hinder their growth and can make their future cash flows appear less valuable.