A final question concerns what money markets will look like in the aftermath of the crisis. The crisis brought a significant reduction in money market activity, due to a combination of perceptions of credit risk and large amounts of excess liquidity arising from central bank crisis measures. Going forward it appears likely that there will be a shift towards secured interbank activity.
This raises the question whether central banks should change their operational target, which is generally a short-term unsecured rate, to a secured rate. 25  In the textbook, that bound is given by zero. In practice, however, the bound may arise at low but non-zero interest rate.