|Here are some stats for you.|
the negative effects of Congress over long-term returns are well-documented. In a report from Professor Michael Ferguson from the University of Cincinnati and Dr. Douglas Witte from the University of Missouri, Congress activity is found to have a strong relationship with lower stocks returns and higher volatility. In contrast, returns are higher and volatility is lower when Congress is not in session.
The so-called “Congressional Effect” accumulates impressively over time. Between 1897 and 2006, more than 90 percent of the capital gains in the Dow Jones Industrial Average came on days when Congress was out of session. Going back to 1957, the S&P 500 has logged more than two-thirds of its rise when Congress was not in session.