Taking account of this uncertainty is particularly important in the case of the euro area, whose “deep structural parameters” are somewhat uncertain to the extent that the inception of the euro may have been associated with a “regime shift”. More prosaically, this medium-term orientation of the single monetary policy recognises that it is impossible for a central bank to control price developments with accuracy over the short-term. The second implication is that the relevant indicators for monetary policy must reflect, almost exhaustively, the main sources of both short and long-term inflation. In the light of this, the monetary policy strategy seeks, as far as possible, to rely on a “full information approach”. This is what the concepts economic analysis and monetary analysis – also known as the two-pillar approach – used notably at the press conferences given by the ECB President following monetary policy decisions, reflect: -  the economic analysis examines cyclical, economic and financial indicators related to the main determinants of short-term inflation;  -  the monetary analysis, is based on a monetary explanation of the low frequency movement of inflation. -  The medium-term orientation of the single monetary policy makes necessary the crosschecking of these two complementary approaches. From this point of view, the ECB’s monetary policy strategy is more comprehensive than pure inflation or monetary targeting strategies.
However, there remain two causes for concern: -  one is the natural difficulty in moving to an entirely new set of price references – and it may take a number of years before this switch is fully made by the public at large. -  and the second, probably related to the first one, is the feeling in the public that there have been excessive price increases linked to the cash changeover. Indeed, the public’s attention has focused on a small number of goods and services in which abnormal increases occurred at the time of this event, leading to a misperception of the real rate of inflation. This gap between perceived inflation and real inflation has however been narrowing progressively and should hopefully disappear in the near future. Concluding remarks To conclude, let me emphasise that eight years after its adoption, the euro has lived up to all of our expectations. After the unprecedented challenge of a continent-wide cash changeover, the euro almost instantly replaced the legacy currencies without any disruptions. It has fostered both price and macroeconomic stability through its credibility and has shielded many euro area countries from significant exchange rate volatility and financial market  1  On average, central banks of industrialised countries changed their policy rates every 5 months both in the 1980s and the 1990s (Source Clerc et Yates (1999): “Interest rate stepping: some puzzles and facts”, mimeo Bank of England), which is close to the frequency of the ECB interest rate changes (4.7 months).