Quantitative easing (QE) is a type of monetary policy used by central banks to stimulate the economy when standard monetary policy has become ineffective.[1][2][3] A central bank implements quantitative easing by buying specified amounts of financial assets from commercial banks and other private institutions, thus raising the prices of those financial assets and lowering their yield, while simultaneously increasing the monetary base.[4][5] This differs from the more usual policy of buying or selling short-term government bonds in order to keep interbank interest rates at a specified target value.