As you know, in the latter part of 2008 and early 2009, the Federal Reserve took extraordinary steps to provide liquidity and support credit market functioning, including the establishment of a number of emergency lending facilities and the creation or extension of currency swap agreements with 14 central banks around the world.

Clear communication is always important in central banking, but it can be especially important when economic conditions call for further policy stimulus but the policy rate is already at its effective lower bound.

Imperfect substitutability of assets implies that changes in the supplies of various assets available to private investors may affect the prices and yields of those assets.

Ben Bernanke Quotes