When the economy slows down, interest rates tend to go down as well. This is because central banks, such as the Federal Reserve in the United States, will lower interest rates in order to stimulate the economy. Lowering interest rates makes it cheaper for businesses to borrow money, which can help to fuel economic growth. Lower interest rates also tend to make it easier for consumers to borrow money, which can help to increase spending and stimulate the economy. The opposite is true when the economy is doing well; interest rates tend to go up as central banks try to prevent the economy from overheating.