The biggest surprise in Figure 2 is how late and how little the zero bound appears to have constrained the two-year Treasury yield after 2008. Only beginning in 2011 did yields of this maturity become significantly less sensitive than normal to news. Even then, they continued being partially responsive until late 2012. Thus, to the extent that the Fed can influence monetary policy expectations over a two-year horizon, the implication is that monetary policy was about as effective as usual until at least late 2011.