This paper presents a toolkit1 for generating optimal policy projections. It makes five contributions. First, the toolkit requires a minimal set of inputs: only a baseline projection for target and instrument variables and impulse responses of those variables to policy shocks. Second, it solves...

Negative interest rates remain a controversial policy for central banks. We study a novel signalling channel and ask under what conditions negative rates should exist in an optimal policymaker’s toolkit. We prove two necessary conditions for the optimality of negative rates: a time-consistent...