On the negatives of negative interest rates and the positives of exemption thresholds

Major central banks remunerate reserves at negative interest rates and it is increasingly likely that they will keep rates negative for many more years. To study the long run implications of negative rates, we construct a dynamic general equilibrium model with commercial banks funding investment projects and a central bank issuing reserves. Negative rates distort investment decisions resulting in lower output and welfare. These findings sharply contrast the short-run expansionary effects ascribed to negative rate policies by most of the existing literature. Negative rates also reduce commercial bank profitability. Exempting a fraction of reserves from negative rates can resolve profitability concerns without affecting the central bank's ability to control the money market rate. However, exemption thresholds do no mitigate the investment distortions created by negative rates.