Ex-post and real-time estimations of the output gap: A new assessment of fiscal procyclicality in the eurozone

The revisions implemented twice a year by the European Commission significantly change not only the forecasts but also the past values of the output gap. Consequently, many possible time series exist. Based on a new approach for estimating a real-time definition of the business cycle, we develop a comparative framework between ex-post and real-time variables using dynamic panel data models with FE, GLS and AB estimators. The real-time version of the output gap solves the important endogeneity issue between the budget balance and the output gap. Considering the period from 1995 to 2021 and the 19 Eurozone countries, our analysis deepens the cyclical nature of fiscal policy, pointing to robust procyclicality. Regardless of the specification, fiscal policy was found to be procyclical, but real-time and ex-post estimates have shown some interesting discrepancies (i.e., on a real-time basis, discretionary budgetary decisions have never been significantly expansionary, and the likely positive effects of automatic stabilisers during economic downturns have been weakened by spending reductions and/or revenue increases). Our findings may help the future reform of the Stability and Growth Pact.