On top of that, it looks like the Federal Reserve's market-stimulating interest rate cut has come to an end. Anything that put stocks in the red.
For the month of October, all three main indices are up. Nasdaq gained the most at 3.7%, followed by S&P with 2.1%. The Dow rose just 0.5% during the month.
Financial markets have been rising and falling with trade headlines throughout the year. Since the summer, the Federal Reserve's decision to stimulate the slow US economy with interest rate cuts has also been a positive backdrop for equities.
Although the Fed acknowledged the risks to the world economy, it also said that America was still doing well in comparison.
But poor financial data continues to seep in: earlier Thursday, the Institute of Supply Management's Chicago Business Barometer reached its lowest level since December 2015. It was the second reading below 50, which marks the boundary between growth and contraction.
Benchmark rates set by central banks largely affect financial institutions and seep into the economy through them. They are not the same as the interest rates a country pays on its debt, which is driven by factors such as risk sentiment. In particular, government bonds in the US, Japan and Germany are considered safe haven investments and are popular in times of market problems.
Central banks in both the EU and Japan kept interest rates at extremely low levels, although economic growth has been slow at best.
Correction: An earlier version of this story omitted a word from President Trump's tweet.