If the Fed increases the money supply, short$-$term interest rates tend to decline.

When the economy is weakening, the Fed is likely to increase short$-$term interest rates.

During the credit crisis of $2008,$ investors around the world were fearful about the collapse of real estate markets, shaky stock markets, and illiquidity of several securities in the United States and several other nations. The demand for U$.$S$.$ Treasury bonds increased, which led to a rise in their price and a decline in their yields.