Traders pile out of bank stocks

The financials were Fed day's biggest losers, as bank stocks saw big losses on big trading volumes.

What's happening: Bank of America was the 2nd most actively traded stock in the S&P 500, with 81 million shares changing hands, per FactSet — well above the 3-month average volume of 67 million shares. The stock fell 3.4%.

Meanwhile, Goldman Sachs was the biggest decliner in the Dow on Wednesday. Shares fell 3.38% after the Fed said it would hold rates steady and signaled the end of rate hikes for the rest of the year.

• More than 5.2 million Goldman shares were traded, the highest trading volume since Jan. 31. That was the day after the Fed first introduced the word "patient" in its FOMC statement.

JPMorgan and Citi also saw slightly higher trading activity than in previous days this week, with 14 million and 17 million shares exchanged, respectively.

• Only 2 stocks in the S&P 500's financial sector closed in the green: Ameriprise Financial and MSCI.

The big picture: A low-interest rate environment is seen as negative for bank stocks.

• "Lower interest rates ... [do] hurt banks in terms of their net interest margins and their profitability on new loans ... [and] that's probably the concern more on a bank’s earnings fundamentals in terms of potential slowing in earnings growth," Paul Eitelman, a strategist at asset management firm Russell Investments, told Bloomberg.

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