*  *  *  The financial and economic crisis that started in 2007 tested central banks as they had not been tested for many decades. We needed to take swift and decisive action to limit the damage to the economy from the spreading distress in financial markets.
Because the financial distress was so deep and pervasive and because it took place in financial markets whose structure had evolved dramatically, our actions also needed to be innovative if they were to have a chance of being effective. Many central banks made substantial changes to traditional policy tools as the crisis unfolded.