In general, post election year returns for the Dow Jones Industrial Average have been somewhat muted. On average, the best returns in the post election year have occurred from late March through early August. Chart of the Day notes that the post election year returns tend to be weaker because:
"...the party in power will tend to make the more difficult economic decisions in the early years of a presidential cycle and then do everything within its power to stimulate the economy during the latter years in order to increase the odds of re-election."
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Source: Chart of the Day