So, now the ECB has celebrated its anniversary, its 25th anniversary, extensively. But there is no time to rest.

On June 15, in three weeks, the next interest rate decision is due. At 7 percent, the inflation rate in the euro area is still far too high. This is a serious issue. There is no way around the fact that the central bank must continue to raise interest rates.

As things stand at the moment, further interest rate hikes of 0.25 percentage points each are planned in June and July. Savers will be pleased: The first experts are already expecting that the overnight interest rates of some banks could soon exceed the limit of 4 percent.

But the more the central bank raises interest rates, the more the unpleasant consequences of monetary tightening will be felt. The ECB is curbing demand, which is slowing down growth. It is therefore to be expected that the approval of interest rate hikes will no longer be as unanimous as it was last year. As we know from the United States, discussions will soon begin as to when the ECB should take a break.

But if inflation is proving so stubborn, monetary policy needs to be even more persistent. We know from history that the fight against inflation often becomes particularly difficult in the last percentage points. The praise from the birthday party for being an "anchor of stability" will have to be earned by the ECB again.