Anton A. Nakov

The paper documents models used to analyse the interactions and trade-offs between price and financial stability at the European Central Bank. The paper describes a simple conceptual framework to think about the short- and medium-term trade-offs between price and financial stability. Short-term trade-offs arise whenever current inflationary pressure is high, but the financial system is experiencing stress. Medium-term trade-offs arise whenever current inflationary pressure is low, but risk is building up in the financial system. We document four main sets of models used to quantify trade-offs: time series models, balance sheet models, credit risk models and DSGE models with banking and financial frictions.

The repeated occurrence of supply-chain disruptions since the COVID-19 pandemic reveals the need to complement traditional macroeconomic frameworks with approaches that better capture the complexity of modern economic productionstructures. This paper synthesises the findings of the ChaMP Research Network, highlighting how production network models and heterogeneity across firms, sectors and countries enrich our understanding of monetary policy transmission. Bycapturing input-output relationships between firms and economic sectors, these approaches show how the propagation and persistence of shocks depend on network structure, the position of sectors within the network – where central sectorsexert disproportionate influence – and differences and variations in price and wage flexibility. The inflationary effects of supply shocks tend to be amplified, while the effects of demand shocks, including monetary policy shocks, are dampened. Inaddition, large shocks can give rise to nonlinearities, such as a steepening of the Phillips curve. This aligns with the conclusions of the ECB’s most recent strategy assessment, which emphasise the need to analyse the risks surrounding the inflationoutlook. The findings also point to the emergence of trade-offs between inflation and output gap stabilisation, as production networks and heterogeneity weaken the alignment between price and output dynamics. As a result, stabilising inflation andoutput simultaneously calls for astute fiscal policy. Overall, incorporating production networks provides a more nuanced and policy-relevant framework for designing state-contingent and data-informed monetary policy.

The paper documents models used to analyse the interactions and trade-offs between price and financial stability at the European Central Bank. The paper describes a simple conceptual framework to think about the short- and medium-term trade-offs between price and financial stability. Short-term trade-offs arise whenever current inflationary pressure is high, but the financial system is experiencing stress. Medium-term trade-offs arise whenever current inflationary pressure is low, but risk is building up in the financial system. We document four main sets of models used to quantify trade-offs: time series models, balance sheet models, credit risk models and DSGE models with banking and financial frictions.

We study the implications of climate change and the associated mitigation measures for optimal monetary policy in a canonical New Keynesian model with climate externalities. Provided they are set at their socially optimal level, carbon taxes pose no trade-offs for monetary policy: it is both feasible and optimal to fully stabilize inflation and the welfare-relevant output gap. More realistically, if carbon taxes are initially suboptimal, trade-offs arise between core and climate goals. These trade-offs however are resolved overwhelmingly in favor of price stability, even in scenarios of decades-long transitions to optimal carbon taxation. This reflects the untargeted, inefficient nature of (conventional) monetary policy as a climate instrument. In a model extension with financial frictions and central bank purchases of corporate bonds, we show that green tilting of purchases is optimal and accelerates the green transition. However, its effect on CO2 emissions and global temperatures is limited by the small size of eligible bonds’ spreads.

We study the implications of climate change and the associated mitigation measures for optimal monetary policy in a canonical New Keynesian model with climate externalities. Provided they are set at their socially optimal level, carbon taxes pose no trade-offs for monetary policy: it is both feasible and optimal to fully stabilize inflation and the welfare-relevant output gap. More realistically, if carbon taxes are initially suboptimal, trade-offs arise between core and climate goals. These trade-offs however are resolved overwhelmingly in favor of price stability, even in scenarios of decades-long transition to optimal carbon taxation. This reflects the untargeted, inefficient nature of (conventional) monetary policy as a climate instrument. In a model extension with financial frictions and central bank purchases of corporate bonds, we show that green tilting of purchases is optimal and accelerates the green transition. However, its effect on CO2 emissions and global temperatures is limited by the small size of eligible bonds’ spreads.

Since the European Central Bank’s (ECB’s) 2003 strategy review, the importance of macro-financial amplification channels for monetary policy has increasingly gained recognition. This paper takes stock of this evolution and discusses the desirability of further incremental enhancements in the role of financial stability considerations in the ECB’s monetary policy strategy. The paper starts with the premise that macroprudential policy, along with microprudential supervision, is the first line of defence against the build-up of financial imbalances. It also recognises that the pursuit of price stability through monetary policy, and of financial stability through macroprudential policy, are to a large extent complementary. Nevertheless, macroprudential policy may not be able to ensure financial stability independently of monetary policy, because of spillovers originating from the common transmission channels through which the two policies produce their effects. For example, a low interest rate environment can create incentives to engage in more risk-taking, or can adversely impact the profitability of financial intermediaries and hence their capacity to absorb shocks. The paper argues that the existence of such spillovers creates a conceptual case for monetary policy to take financial stability considerations into account. It then goes on to discuss what this conclusion might imply in practice for the ECB. One option would be to exploit the flexible length of the medium-term horizon over which price stability is to be achieved. Longer deviations from price stability could occasionally be tolerated, if they resulted in materially lower risks for financial stability and, ultimately, for future price stability. However, model-based quantitative analysis suggests that this approach may require impractically drawn-out periods of deviation from price stability and potentially result in a de-anchoring of inflation expectations. ...

We study monetary transmission in a model of state-dependent prices and wages based on ‘control costs’. Stickiness arises because precise choice is costly: decision makers tolerate errors both in the timing of adjustments, and in the new level at which the price or wage is set. The model is calibrated to microdata on the size and frequency of price and wage changes. In our simulations, money shocks have less persistent real effects than in the Calvo framework; nonetheless, the model exhibits a substantial degree of non-neutrality, driven mainly by wage rigidity. State-dependent nominal stickiness implies a flatter Phillips curve as trend inflation declines, because price and wage adjustments become less frequent, making short-run inflation less reactive to shocks. Our model can explain almost half of the observed decline in the slope of the Phillips curve since 2000.

This report discusses the role of the European Union’s full employment objective in the conduct of the ECB’s monetary policy. It first reviews a range of indicators of full employment, highlights the heterogeneity of labour market outcomes within different groups in the population and across countries, and documents the flatness of the Phillips curve in the euro area. In this context, it is stressed that labour market structures and trend labour market outcomes are primarily determined by national economic policies. The report then recalls that, in many circumstances, inflation and employment move together and pursuing price stability is conducive to supporting employment. However, in response to economic shocks that give rise to a temporary trade-off between employment and inflation stabilisation, the ECB’s medium-term orientation in pursuing price stability is shown to provide flexibility to contribute to the achievement of the EU’s full employment objective. Regarding the conduct of monetary policy in a low interest rate environment, model-based simulations suggest that history-dependent policy approaches − which have been proposed to overcome lasting shortfalls of inflation due to the effective lower bound on nominal interest rates by a more persistent policy response to disinflationary shocks − can help to bring employment closer to full employment, even though their effectiveness depends on the strength of the postulated expectations channels. Finally, the importance of employment income and wealth inequality in the transmission of monetary policy strengthens the case for more persistent or forceful easing policies (in pursuit of price stability) when interest rates are constrained by their lower bound.

We study the effects of monetary shocks in a model of state-dependent price and wage adjustment based on “control costs”. Suppliers of retail goods and of labor are both monopolistic competitors that face idiosyncratic productivity shocks and nominal rigidities. Stickiness arises because precise decisions are costly, so agents choose to tolerate small errors in the timing of adjustments. Our simulations are calibrated to microdata on the size and frequency of price and wage changes. Money shocks have less persistent real effects in our state-dependent model than they would a time-dependent framework, but nonetheless we obtain sufficient monetary nonneutrality for consistency with macroeconomic evidence. Nonneutrality is primarily driven by wage rigidity, rather than price rigidity. State-dependent nominal rigidity implies a flatter Phillips curve as trend inflation declines, because nominal adjustments become less frequent, making short-run inflation less reactive to shocks.

We model retail price stickiness as the result of costly, error‐prone decision making. Under our assumed cost function for the precision of choice, the timing of price adjustments and the prices firms set are both logit random variables. Errors in the prices firms set help explain micro facts related to the size of price changes, the behavior of adjustment hazards, and the variability of prices and costs. Errors in adjustment timing increase the real effects of monetary shocks, by reducing the “selection effect.” Allowing for both types of errors also helps explain how trend inflation affects price adjustment.