My guess is a lot of investors are concered, as to what the new government will look like and what goals it will want to set. As the main democratic campaign was based on basically saying we're not republicans so vote for us. They never really road mapped a plan for if they take control of the House and Senate, so investors are unsure what to expect from them. Some democrats could try to push for clean air bills which would result in companies paying millions of dollars to clean up thier pollution or something along these lines which would cut into profits and hurt the economy.

Who Delivers ten times out of ten?