Bank stocks are suffering their worst week in six months, the latest sign that investors remain cautious on the financial sector even as the US economy grows at the fastest pace in years.

The S&P 500 financials sector has fallen 3% this week, on pace for its worst period since March 23, to trim all of its 2018 gains. The decline comes after the group hit a six-month high last week. The more narrow KBW Bank index of 24 bank stocks has also struggled, lagging behind as the broader stock market has hit fresh records.