Historically, the post-election period has been a good one for stocks. "So the question is, 'Did the markets go up in the midterm election years by more than average in non-election years?' Gendreau says. "And the answer is, 'Yes, by a huge amount more.'" The Dow has risen following 19 of the last 22 midterm elections.
Also, after the midterms, there is generally a more balanced share of power between the president and Congress, so the chance for compromise is more likely. "The market seems to like that," he says.
So what about this year? Gendreau is the first to admit that he's not the first economist to release a survey like this. His research just covers a longer period of time. He also notes that given the ever-increasing wealth of information available to traders today, the effects of this trend may be somewhat weaker going forward. But so far this year, the Dow has been steadily rising in anticipation of the midterms, gaining about 7 percent year-to-date.
Looking further out, the year following the midterms or the president's third year in office is usually the best year for the Dow, according to an older study by Gendreau. From 1871 to 2005, the average return of the S&P Composite Stock Index during the third year of a president's term was 10.1 percent. During the fourth year in office the index was up 7.5 percent, on average--a marked improvement over average returns in the first year (3 percent), and the second (2.7 percent).