Financial markets like certainty.

On Tuesday night, as the presidential election’s outcome became far from certain, stock futures plunged. Investors had bet heavily Monday on a victory by Democrat Hillary Clinton. So as Republican Donald Trump picked up many more votes than polls had predicted, markets reacted violently to the change in expectations.

Across the board, it turned ugly for equities, currencies and Treasurys. The CBOE Volatility Index, a measure of investor fear, showed a 30 percent spike.

The shock of a tight presidential race is hitting markets just months after voters in Britain stunned the world with their Brexit vote to leave the European Union.

Throughout the summer and into the fall, U.S. markets were relatively quiet as investors became confident that Clinton would win. Then in late October, when it appeared the FBI would reopen an investigation into questions about Clinton’s email, stocks began a steady fall.

For nine straight days, the S&P500 drifted down. But that sentiment turned around when the FBI said it had found nothing new that would trigger any further action. On Monday, markets rebounded, with investors again becoming confident of a Clinton victory.

Investors generally see her as a well-known figure whose economic policies would be similar to President Obama’s. In contrast, Trump’s positions are less clearly spelled out, and businesses generally oppose his key position — tearing up existing trade agreements.

With so much uncertainty, investors shifted money out of stock futures and into safe havens. The Japanese yen shot up against the U.S. dollar while the Mexican peso fell. Gold rose. Ten-year U.S. Treasurys fell.

As the night wore on with no resolution of the presidential race, markets continued reflect fear and volatility. It seemed a long way to morning.

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