(Bloomberg) -- Falling Treasury yields may have been the straw that broke the camel’s back for investors in an exchange-traded fund stuffed with bank stocks.

Investors yanked $174 million from the iShares U.S. Financial Services ETF, or IYG, on June 19. That’s a record outflow for the fund which -- with over 60 percent of its holdings in U.S. banks -- has the largest exposure among broad financials ETFs. And volume was over $214 million, almost 15 times the average daily turnover in the past year.

Mounting trade war concerns and declining Treasury yields this week have put pressure on bank stocks. The yield on 10-year Treasuries was as low as 2.88 percent Wednesday, the lowest since June 1, putting investors’ hopes for 3 percent on hold.

Bank stocks typically do better when interest rates are rising because the firms can charge more for loans.

The market also may be reacting defensively ahead of the first round of bank stress tests, due to hit after the market close on June 21. The Federal Reserve’s instructions for 2018 Comprehensive Capital Analysis and Review (CCAR) stress tests are being viewed as tougher this year.

Some technical indicators may also be weighing on the fund. Shares of JPMorgan Chase & Co., the largest holding in IYG, are “skittering along” the 200-day moving average ahead of stress test results, which definitely encouraged trading, Dave Lutz, head of ETFs at JonesTrading Institutional Services, wrote in a note.

--With assistance from Olivia Schaber and Tom Lagerman (Global Data).

To contact the reporters on this story: Carolina Wilson in New York City at cwilson166@bloomberg.net;Felice Maranz in New York at fmaranz@bloomberg.net

To contact the editors responsible for this story: Courtney Dentch at cdentch1@bloomberg.net, Eric J. Weiner, Rachel Evans

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