US Presidents as the political leader of the nation can influence the economy through their policies, but their influence to the stock market is very marginal. People will argue when a president from Republican Party with its conservative view on economy will translate to the stock market gain, vice versa, a president from Democratic Party will be bad for the stock market. Let’s take a look at S&P index returns under both Republican and Democratic presidents for the past 60 years, and recessions during that time。