Billionaire Cliff Asness’s quantitative firm, AQR Capital Management, is dismissing between 5% and 10% of its global workforce after its funds underperformed and lost assets last year.

AQR had about 900 employees globally before the cuts, according to a person with knowledge of the firm. Affected employees are being told Wednesday.

“This continues to be a challenging time for the asset management industry,” Suzanne Escousse, AQR’s chief marketing officer, said in an email Wednesday. “After conducting our annual review, we made the difficult decision to reduce headcount to balance the size of our workforce with the current needs of our clients.”

Asset managers are struggling as investors bolt for inexpensive index funds, putting pressure on fees at a time when active investments are underperforming. AQR’s job cuts come a year after it reduced its headcount by a low single-digit percentage. The firm’s assets have fallen by almost 20% to $185 billion in the year ended September 2019, the biggest decline in recent years.

Asness in May said that stock picking by quants had been “terrible.” In the following months, his firm sought to sublet space at its Greenwich, Connecticut headquarters after coming off a tough year in 2018 when most of its funds failed to make money and investors pulled capital.

Asness, 53, co-founded AQR in 1998 and helped popularize risk-parity strategies, which aim to spread risk equally across different asset classes based on historical and expected volatilities to produce smoother returns.

AQR manages about 100 long-only and alternative funds. Among the biggest is its $2.1 billion Style Premia Alternative Fund lost 8.2% last year, underperforming a U.S. Three-month Treasury bill index, according to the firm’s website. Its $4.4 billion Managed Futures Strategy Fund gained 1.9%, trailing the same benchmark, the website showed.

Some of AQR’s smaller funds have done better. Its $245 million International Defensive Style Fund gained 18.4% last year, while its Multi-Asset fund rose 21%, according to the website. It has $137 million in assets.

Escousse said Wednesday that firm remains committed to “our investment philosophy, process and strategies, and believe that today’s action contributes to the long-term health and strength of our business.”

This article was provided by Bloomberg News.