(Bloomberg) -- Friday was a difficult day for most investors. For U.S. mutual funds with a significant share of their money in European bank stocks, it was especially brutal.

The five worst-performing major equity funds -- each of which lost about 10% -- focus on international investing and hold anywhere from 12% to 20% of their assets in bank stocks. Those shares tumbled as global markets sold off after voters in the U.K. decided to exit the European Union.

“I don’t think the intrinsic value of these stocks has fallen anywhere near as much as Mr. Market has reduced their prices,” David Herro, manager of the $23 billion Oakmark International Fund, said in a Bloomberg Television interview on Friday.

Herro’s fund dropped 9.7% for the day, making it the third-worst performer among almost 1,000 U.S.-based equity funds with at least $1 billion in assets, according to data compiled by Bloomberg. Funds focusing exclusively on Europe were excluded.

Banks have born the brunt of the selloff as investors worry that the British decision will translate into slower global growth and heightened market volatility. The climate of uncertainty means central banks are likely to keep interest rates lower for longer, which hurts earnings at financial companies.

The funds that slid the furthest Friday also include the $2 billion Federated International Leaders Fund, the $1.6 billion JPMorgan International Value Fund, the $2.9 billion Principal Overseas Fund and the $2.5 billion American Beacon International Equity Fund.

FURTHER SELLING

Financial stocks within the MSCI EAFE Index, which tracks developed markets in Europe and Asia, sank 10% on Friday and an additional 5% on Monday. They were the worst-performing group both days, according to data compiled by Bloomberg.

Swiss lender Credit Suisse Group AG lost 14% on Friday, its biggest plunge since December 2008, and 9.2% on Monday. Paris-based BNP Paribas SA dropped 17% on Friday and 6.3% today.

Kimberly Glennon, a spokeswoman for Oakmark, declined to comment on performance, as did Kristen Chambers, a spokeswoman for JPMorgan Chase & Co. The other fund companies didn’t respond to messages or said no one was available for comment.

Herro, in the Bloomberg TV interview, said global banks are much stronger now than they were during the 2008 financial crisis because they have larger capital cushions and their customers are benefiting from low interest rates and energy prices.

“The banks are much better positioned to weather the uncertainties,” he said.

Oakmark International, which trails 99% of its Bloomberg peers in 2016, outperformed 56% of competitors over the past five years. Herro was named international stock manager of the decade by Morningstar Inc. in 2010.

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