Quantitative easing is an example of monetary policy, which is generally used when interest rates are zero. During the 2008 credit crisis, market values of mortgage-backed securities had substantially due to the default rate on mortgages. In an attempt to restore investor faith in the securities, the Federal Reserve engaged in by mortgage-backed securities. Consequently, the prices of these securities and investors began to purchase the risky debt securities, which resulted in liquidity in the market for these securities