摘要:We study the convergence properties of inflation rates among the countries of
the European Monetary Union over the period 1980-2004. Given the Maastricht
agreements and the adoption of the single currency, the sample can be naturally
split into two parts, before and after the birth of the euro. We study
convergence in the first subsample by means of unit-root tests on inflation
differentials, arguing that for testing absolute convergence, a power gain is
achieved if the Dickey-Fuller regressions are run without an intercept term. We
find evidence for the convergence hypothesis over the period 1980-97 and a clear
indication of the important role played by the Exchange Rate Mechanism (ERM) in
strengthening the convergence process. We then investigate whether the second
subsample is characterized by stable inflation rates across the European
countries. Using stationarity tests on inflation differentials, we find evidence
of diverging behavior. In particular, we can statistically detect two separate
clusters, or stability clubs: (i) a lower-inflation group that comprises
Germany, France, Belgium, Austria, and Finland and (ii) a higher-inflation one
with Spain, the Netherlands, Greece, Portugal, and Ireland. Italy appears to
form a cluster of its own, standing between the other two.