In 2016, Lee Bohl, a Charles Schwab researcher, analyzed market data between 1933 and 2015, and found that, in general, the third year of the presidency overlapped with the strongest market gains.4 The S&P 500, a fairly broad index of stocks, exhibited the following average returns in each year of the presidential cycle since 1933:
Year after the election: +6.7%
Second-year: +5.8%
Third-year: +16.3%<==
Fourth-year: +6.7%
https://www.investopedia.com/terms/p/presidentialelectioncycle.asp#citation-13