On top of all the other obstacles thrust on investors for 2018 comes one that has been a burden for decades: the upcoming midterm elections that will determine the direction of Congress.
The races for the House and Senate as well as state governorships and legislatures have been a headache for the market going back to World War II.
In the period since, the S&P 500 has declined 2.2 percent in the second quarter and 0.9 percent for the third quarter in midterm election years. Those are the only two negative periods in the presidential cycle, according to Sam Stovall, chief investment strategist at CFRA.
"During mid-term election years, one word tends to describe investors' mindset and the driving force behind share-price performances: uncertainty," Stovall said in a research note. "It is therefore not surprising to see that the two quarters leading up to the mid-term elections have been the most challenging of the entire 16-quarter presidential cycle."