We consider a model-averaged forecast-based estimate of the output gap to measure economic slack in 10 industrialized economies. Our measure takes changes in the long-run growth rate into account and, by addressing model uncertainty using equal weights on different forecast-based estimates, is robust to different assumptions about the underlying structure of the economy. For all 10 countries in the sample, we find that the estimated output gap has much larger negative movements during recessions than positive movements in expansions, suggesting business cycle asymmetry is an intrinsic characteristic of industrialized economies. Furthermore, the estimated output gap is always strongly negatively correlated with future output growth and unemployment and positively correlated with capacity utilization. It also implies a convex Phillips Curve in many cases. The model-averaged output gap is reliable in real time in the sense of being subject to relatively small revisions.

In this article, I evaluate the challenges related to the European Commission's output gap method of calculating the structural budgetary position, and assess its bottom-up alternatives in the EU's fiscal framework using the Finnish data for the years 1984–2014. The results reinforce the impression of the limited capacity of the output gap method to predict cyclical changes in real time and suggest that using the output gap method to steer fiscal policy tends to lead to a procyclical policy (stimulus in upturns and austerity in downturns). The bottom-up assessment methods that are based on discretionary fiscal policy measures appear to work better, and using them to steer fiscal policy could make the policy more effective.

This paper investigates the interactions between three key macroeconomic imbalances, namely current-account discrepancies (external imbalances), output gaps (internal imbalances), and exchange-rate misalignments. We estimate a panel VAR model for a sample of 22 industrialized countries over the period 1980–2011. Our findings show that macroeconomic imbalances strongly interact through a causal relationship. If current-account disequilibria threaten the stability of the global economy, their origin can be found in internal imbalances and exchange-rate misalignments: positive output-gap shocks as well as currency overvaluation deepen current-account deficits. In addition, although variations in external imbalances mainly result from exchange-rate misalignments in the euro area, they are mostly explained by output gaps for non-eurozone members.

Alternative measures of the UK output gap are considered for 1984–2007. The real-time series is strongly affected by the rolling-time estimation of the trend, and produces a picture of the business cycle which is not consistent with contemporary perceptions of the large fluctuations of the late 1980s and early 1990s. A new, ‘nearly-real’, measure developed here may be better for estimating historical reaction functions. In the context of the current recession, none of these mechanically derived measures of the output gap are useful. Policymakers should make careful estimates of the likely fall in potential output on the basis of other information.

A long-standing area of research and policy interest is the construction of a measure of monetary policy stance. One measure that has been proposed, as an alternative to indices that employ monetary aggregates or exchange rates, is the spread between the actual real interest rate and its flexible-price, or natural-rate, counterpart. We examine the properties of the natural real interest rate and real-interest-rate gap using a dynamic stochastic general equilibrium model. Issues we investigate include the response of the gap and its components to fundamental economic shocks and the indicator and forecasting properties of the real-interest-rate gap for inflation, both in the model and in the data. Our results suggest that the real-interest-rate gap has value as an inflation indicator, supporting a neo-Wicksellian framework.