Central banks and interest rates

Central bank decisions are usually the most important scheduled events on the economic calendar. Interest rates affect what investors earn from holding a currency, so changes in rates — and in expectations about future rates — can move exchange rates significantly. This lesson explains what central banks do and how to read their communications.

What a central bank is trying to do

A central bank manages a country's or region's monetary policy. For most of the major banks, the core aim is price stability, usually defined as inflation of around 2% over the medium term. Some have additional goals; the US Federal Reserve, for example, has a dual mandate covering maximum employment as well as stable prices.

The main tool is the policy rate — a short-term interest rate the central bank sets or targets. Broadly:

• Raising rates (tightening) makes borrowing more expensive and is used to slow inflation.
• Cutting rates (easing) makes borrowing cheaper and is used to support a weakening economy.

Central banks also use other tools, such as buying or selling government bonds, but the policy rate is the one traders watch most closely.

Four examples of major central banks

Each of these holds around eight scheduled policy meetings a year, with dates published well in advance on any economic calendar.

Why rates move currencies

All else being equal, a currency offering a higher interest rate is more attractive to hold, because deposits and bonds in that currency pay more. When a central bank raises rates — or signals that it will — demand for its currency can rise.

The key word is expectations. Markets constantly price in where they think rates are heading. If a 0.25 percentage point rise is fully expected, the decision itself may barely move the currency. The bigger reaction often comes from information that changes the expected future path.

Worked example: a rate decision in basis points

Interest-rate changes are often quoted in basis points, where 1 basis point = 0.01 percentage point, so 100 basis points = 1 percentage point.

Suppose, as an illustration, a central bank's policy rate is 4.00% and markets expect a cut of 25 basis points.

• Expected new rate: 4.00% − 0.25% = 3.75%
• If the bank cuts by 50 basis points instead: 4.00% − 0.50% = 3.50%, a 25-basis-point surprise in the easing direction.
• If the bank holds at 4.00%: that is a 25-basis-point surprise in the tightening direction, even though nothing changed.

This is why "no change" can still move a market sharply.

Reading the communication

The rate decision is only part of the event. Each bank publishes material that traders read closely.

The policy statement

Released with the decision, the statement explains the reasoning. Traders compare the wording with the previous statement line by line, because small changes — such as dropping a phrase about "further increases" — can signal a shift.

The press conference

The Fed, ECB and BoJ heads usually hold a press conference after each policy meeting, and the BoE holds one alongside its quarterly Monetary Policy Report. Answers to journalists' questions can move markets more than the decision itself, so volatility often continues well after the release.

Votes, projections and minutes

• Some banks publish how each committee member voted. A split vote can hint at a coming change.
• Many publish economic projections. The Fed's quarterly projections include each participant's expected path for rates, often called the "dot plot".
• Minutes or accounts of the meeting, published later, give more detail on the debate.

Forward guidance

Forward guidance is a central bank's communication about the likely future path of policy. It can be explicit ("we expect rates to remain at this level for some time") or conditional ("further tightening may be needed if inflation remains high"). Central banks use it to shape expectations gradually, rather than shocking markets.

Two practical points:

• Guidance is not a promise. Banks regularly say decisions are "data dependent", which means upcoming inflation and jobs releases can change the path. This links central banks directly to the data covered in the next lesson.
• Speeches by committee members between meetings can also move currencies, so check the calendar for scheduled appearances.

Key takeaways

• Most major central banks target inflation of around 2% and use a short-term policy rate as their main tool.
• Currencies react to changes in expected rates; a decision that matches expectations may cause little movement, while "no change" can be a surprise.
• One basis point is 0.01 percentage point; 25 basis points is 0.25 percentage point.
• The statement, press conference, votes and projections often matter as much as the decision itself.
• Forward guidance shapes expectations, but it depends on incoming data and can change.