New York (CNN Business) A growing number of economists predict that the United States will experience a recession sometime later this year or in 2020. Investors are starting to worry about a downturn, too.

About three quarters (73%) of investors expect a recession within the next two years, according to a survey of 260 professional money managers and analysts done late last year by Boston Consulting Group. In 2017, just over half (53%) thought a recession was coming.

The current attitude has little to do with China trade, Brexit or the government shutdown in Washington.

Instead, investors are most nervous about market valuations and central bank policies. Nearly two-thirds (64%) of the bearish investors said that current stock prices were making them worried and about half (48%) said interest rate levels concerned them.

It will be interesting to see if these worries begin to fade, though.

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