In the month following the end of the closure, the S&P 500 index typically shows positive returns. For example:

• During the government shutdown in 1995-96 (21 days), the return was approximately -0.03%, and it rose by about +4.01% one month after the shutdown ended.
During the government shutdown in October 2013 (17 days), the return was approximately +2.33%, and about +4.54% one month after it ended.
During the long closure in 2018-19 (35 days), the return was approximately +10.07%, and about +5.09% in the month following the closure.
• Most analyses suggest that regardless of market performance during the closure, it usually rebounds or recovers after the closure ends.