Lackluster fourth quarter results, along with weak consumer confidence data, caused U.S. equities and stock exchange traded funds to weaken Tuesday, notably in the technology and industrial sectors.

The S&P 500 Index, along with related funds including the SPDR S&P 500 ETF (NYSEArca: SPY), iShares Core S&P 500 ETF (NYSEArca: IVV) and Vanguard 500 Index (NYSEArca: VOO), were 0.4% lower Thursday.

The sell-off Tuesday occurred right after Wall Street experienced its worst day of 2017 as investors showed concern over President Donald Trump’s isolationist policies, like stopping travel to the U.S., reports Yashaswini Swamynathan for Reuters.

Investors also tried to assess the implications of Trump’s firing late Monday of acting attorney general in retaliation for her refusal to defend his executive order on halting immigration.

“There are a number of things happening at the same time—the travel ban, the [potential]increase in tariffs, inflation in Europe, a bit of weakness in the U.S. GDP print,” Shannon Saccocia, head of asset allocation at Boston Private Wealth, told the Wall Street Journal. “Each of those individually probably isn’t enough to upend the market trajectory, but all of them coming at the same time is creating enough uncertainty for a pullback.”

The tech and industrial sectors led markets lower, with the Technology Select Sector SPDR (NYSEArca: XLK) down 0.8% and Industrial Select Sector SPDR (NYSEArca: XLI) down 1.2%.

“Many technology CEOs have come out publicly against Trump’s immigration policies and it certainly hurts the sector’s access to highly qualified labor,” Brant Houston, portfolio manager at Atlantic Trust, told Reuters.

Silicon Valley has shown a history of bringing promising individuals from foreign countries into the U.S.

Apple (NasdaqGS: AAPL), Facebook (NasdaqGS: FB) and Amazon.com (NasdaqGS: AMZN) are among the major U.S. tech companies due to reveal fourth quarter results this week.

Meanwhile, a report from the Conference Board revealed the consumer confidence index dipped by a larger-than-expected margin in January after touching a 15-year high in December, further dragging on market sentiment.

Nevertheless, this earnings season has been good for the equities market, with 73% of S&P 500 companies that have reported showing better-than-expected profits.

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