U.S. markets were also fluctuating in mixed trading Monday partially due to  escalating tensions between the U.S. and North Korea after South Korea and U.S. forces engaged in computer-simulated war game exercises Monday.

“I think (the market’s decline) is a continuation of the weakness we’ve seen in the last couple of weeks,” Paul Nolte, portfolio manager at Kingsview Asset Management, told Reuters. “We have come off a really strong period for the market and are really just digesting the gains.”

Analysts still expect the U.S. economy to be supportive of the ongoing bull market rally in equities as growth is fast enough to bolster corporate earnings but slow enough to keep the Federal Reserve from tightening its monetary policy too quickly.

“Equity markets don’t just decline unless you have concerns that growth is going to decelerate—and there’s very little to suggest that at this point,” Jeremy Zirin, head of investment strategy Americas at UBS Chief Investment Office, told the WSJ.

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