Global protectionism, including threats coming from the United States, pose a big risk to global economic growth, the head of Canada’s second-largest pension fund said Friday.

“If you begin to see meaningful protectionism I personally believe you’re going to see a significant pause in a lot of business investment,” Caisse de dépôt et placement du Québec CEO Michael Sabia said after unveiling the institutional investors’ 2016 results.

“You will see many fewer companies wanting to commit capital and wanting to expand because it’s just too uncertain.”

Read: Michael Sabia to remain as head of Caisse de dépôt

Quebec’s main public pension fund manager earned a 7.6% return on investments last year, its worst performance in five years.

While the U.S. stock market has reached record highs, Sabia said investors haven’t priced in unprecedented geopolitical risks, including uncertainties over actions by the Trump administration, upcoming elections in Europe, the implications of Brexit, an influx of refugees to Western Europe and changing economic conditions in China.

He said it’s also not clear whether corporations will be spurred by promises of tax cuts and deregulation to engage in a wave of investments that could boost economic growth.

Sabia said the Caisse has tried to build a portfolio that can weather any challenges by being prudent. He said the pension fund is prepared to pounce on investment opportunities, including those that result from plans for massive infrastructure spending in the United States.

However, Sabia said it’s not certain that congressional Republicans will support President Donald Trump’s desire for US$1 trillion in spending to build roads, bridges and airports.

And while Trump’s recent statement that he’s only looking to tweak NAFTA is probably good news for Canada, the new administration has said a lot but not taken many concrete decisions on economic issues, he told reporters.

“So until we begin to see the completion of the things being done it’s hard to judge how the new administration is going to play their cards.”

The Caisse said net assets grew to $270.7 billion as of Dec. 31, adding $18.4 billion in net investment returns and $4.3 billion net deposits from public pension and insurance plan members.

The annual result was better than the 5.8% return for its benchmark portfolio, but less than the 9.1% earned in 2015. In fact, it was the lowest return since 2011.

Over five years, the Caisse has generated a 10.2% annualized return, adding $100 billion to the institutional investor’s assets.

Sabia said he is “extremely comfortable” with the Caisse’s performance even though it couldn’t immunize itself from global changes, including slow growth exacerbated by low business investment.

“The world is a challenging place and generating returns today is a tough business,” he said.

“Returns are going to step by step be harder and harder to generate and we’re seeing that around the world. And that’s going to be the new reality of the next number of years.”

Last year’s growth was driven by equity investments and a recovery in oil and commodity prices. A strong performance by the Canadian stock market and investments in companies with high U.S. exposure such as Alimentation Couche-Tard, Gildan and Magna generated a 22.7% return.

Real estate and infrastructure investments raked in a 10.6% return while fixed income lagged with a 2.9% return amid low interest rates.

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