NEW YORK (TheStreet) -- U.S. large-cap stock indices remained in tight trading ranges Wednesday afternoon. The factors driving investors' skittishness were global uncertainties, marked by the approaching Sept. 18 Scottish independence referendum and the possibility of a global shift in interest rates.
Watch the video below to see how U.S. markets are doing in midday trading Wednesday:
The Dow Jones Industrial Average
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"I think people are getting worried about Scotland saying 'yes, we want our independence' and the uncertainty that will surround that. You can almost say that it's the referendum that may have killed the bull," said Sam Stovall, U.S. equity strategist at S&P Capital IQ.
The Bank of England has hinted that it could raise rates sooner than expected amid concerns that the market has been underestimating the odds that a Federal Reserve rate hike could come sooner than later.
"Investors are beginning to worry that it's a global shift and that rates, except for Europe as a whole, might be seeing the start of their long, slow uphill climb. That's like a dark cloud hanging over investors mindsets right," Stovall remarked.