Financial markets respond to much more than official interest rate decisions. A carefully worded speech, an unexpected interview or a subtle change in tone from a central banker can influence investors' expectations within minutes.

Research published by the European Central Bank (ECB) on 24 September 2026 examines how communication between monetary policy meetings affects financial markets. The findings suggest that public statements can sometimes generate reactions comparable to those following official policy announcements.

Why Central Bank Communication Matters

The ECB's Governing Council normally meets to discuss monetary policy approximately every six weeks. Its decisions influence borrowing costs, investment and economic activity throughout the eurozone.

However, central bankers also communicate through speeches, interviews and public appearances between meetings.

These statements provide insights into economic conditions and potential policy changes, helping investors anticipate future interest rate decisions.

ECB economists Klodiana Istrefi, Florens Odendahl and Giulia Sestieri explained that communication outside scheduled meetings plays an important role in shaping market expectations and understanding monetary policy transmission.

Thousands Of Statements Analysed

The researchers examined 304 formal monetary policy announcements and approximately 5,000 speeches and interviews delivered between January 1999 and early 2024. Their analysis included communications from ECB presidents, Executive Board members and senior central bankers representing Germany, France, Italy and Spain. By studying immediate movements in interest rates, stock prices and exchange rates, researchers identified which events significantly affected financial markets.

Approximately 45% of official policy announcements generated statistically significant market reactions. Although individual speeches were less likely to trigger major movements, their combined influence was substantial. More than 300 communication events significantly affected the Euro Stoxx 50 stock index, compared with 117 formal policy announcements.

Three Speeches That Influenced Markets

The study identified several occasions when central bankers' statements changed investors' expectations. In November 2005, ECB President Jean-Claude Trichet indicated that an interest rate increase was approaching. Financial markets responded quickly, and the ECB raised rates the following month.

In June 2019, Mario Draghi suggested that additional monetary stimulus might become necessary if inflation remained weak. Investors subsequently adjusted their expectations towards lower interest rates.

Christine Lagarde prompted another notable reaction in November 2021 when she indicated that the conditions required for raising rates were unlikely to be met the following year. These examples illustrate how public communication can influence financial decisions before formal policy changes occur.

How Different Interest Rates Respond

The research revealed important differences between short-term and long-term market reactions. Official monetary policy announcements generally have a greater cumulative influence on short-term interest rates. However, speeches and interviews become increasingly influential when examining longer-term borrowing costs. For two-year overnight indexed swap rates, the cumulative effects of formal announcements and other communications were relatively similar. At longer maturities, the combined impact of speeches and interviews could reach approximately twice that of official announcements. Researchers also observed that central bankers tend to communicate more forcefully before interest rate increases than before reductions.

What Does This Mean For The Economy?

The researchers examined how unexpected monetary policy tightening affects inflation and unemployment.

Their statistical analysis indicated that tighter monetary policy generally reduces inflation while increasing unemployment. Including information from speeches and interviews helped produce more precise estimates of these economic effects. The findings suggest that communication provides additional evidence for understanding how monetary policy influences financial conditions and economic activity.

Why Investors Should Pay Attention

The study highlights the importance of monitoring central bank communication throughout the year. For investors, businesses and financial analysts, official interest rate announcements provide only part of the information needed to understand monetary policy.

Speeches and interviews can reveal changing economic assessments, influence borrowing costs and reshape expectations before the next scheduled meeting. Understanding these signals can help market participants interpret developments in Europe's financial system and prepare for potential changes in monetary policy.