now nelly lang is the director of the office of financial stability policy and research at the federal reserve board. she is responsible for conducting and coordinating work at the board relating to the analyzing, emerging, and structural ricks to financial stability and developing a macro policy to mitigate systemic risks. >> thank you very much. appreciate the invitation to participate. this is an interesting topic for discussion. i will start with saying these are my own views and not those of the federal reserve board. i'm going to start with a little definition of market liquidity as we've expressed it. market participants have been expressing quite a bit of concern about reduced bond market liquidity which we have interpreted to be, they are not able to buy or sell securities in reasonable quantities at relatively low cost without materially affecting market prices. so at the federal reserve we've been listening to these concerns and we've been monitoring a wide range of liquidity indicators, though no single measure appears able to capture the multiple dimensions. many available