Managed float exchange rate

What is a managed float?

A managed float is an exchange rate that is mostly set by supply and demand in the market, but the central bank steps in from time to time to slow or reverse moves it does not want.

It is also called a dirty float. "Dirty" means the float is not left fully to the market. It does not imply anything illegal.

Formal definition

In a managed float there is no announced target rate and no fixed band. The central bank keeps discretion over when and how it acts. The main tools are:

• Direct intervention. The central bank buys or sells foreign currency, usually US dollars, from its reserves.
• Interest rate policy. A higher policy rate can make holding the local currency more attractive.
• Verbal intervention. Public statements that the bank is watching the market or is ready to act.
• Administrative measures. Rules on who may buy foreign exchange and for what purpose.

Intervention can be sterilised, meaning the central bank offsets its effect on the domestic money supply, or unsterilised, meaning it lets that effect pass through.

Worked example (hypothetical)

Imagine a country whose currency floats against the US dollar.

1. Importers rush to buy dollars before a large oil payment. Demand for dollars rises and the local currency weakens quickly over a few days.
2. The central bank decides the speed of the fall is disorderly. It sells dollars from its reserves to banks, which adds dollar supply.
3. The local currency's slide slows or partly reverses. The central bank does not defend any specific level. It only smooths the move.
4. Weeks later the market keeps pushing the currency weaker at a slower pace, and the central bank lets it go.

What sets this apart from a peg is that the bank never promised a level. Over time the market direction still dominates.

Where the term appears

• News and central bank reports: phrases like "the central bank sold dollars", "reserves fell after intervention" or "to curb excessive volatility".
• IMF classifications: the IMF sorts countries' exchange rate arrangements into categories. What a country says it does (de jure) and what it actually does (de facto) can differ.
• Trading platforms: the term does not appear on charts. Its effects do. Managed currencies can trade quietly for long periods and then move sharply when policy changes. Leveraged CFD and forex trading on such pairs can lose money fast, especially when prices gap.

Edge cases

• Managed float vs crawling peg: a crawling peg adjusts a stated rate by planned steps. A managed float has no stated rate.
• Heavy management: if intervention becomes constant and the rate barely moves, the regime behaves like a soft peg even if it is still called a float.
• Free float with rare intervention: many "free floats" also see occasional intervention. The difference is one of degree.
• Devaluation: this is the formal term for a pegged rate being reset. In a float, the same move is called depreciation.

Related terms

• Currency board
• Bretton Woods system
• Currency appreciation
• Dollarization
• Currency risk
• Emerging markets
• Basis point
• Fundamental analysis
• Trading glossary

Frequent questions

Is a dirty float the same as a managed float?

Yes. Both names describe a floating rate with occasional central bank intervention.

Does a managed float have a target rate?

No. If a target or band is announced, the regime is closer to a peg or a crawling peg.

How do I know if a central bank intervened?

Look at central bank statements, reserve data and news reports. Some intervention is not announced, so price behaviour alone is not proof.

Why do central banks manage instead of fixing the rate?

A managed float lets the rate absorb shocks while the bank keeps the option to limit sharp moves. It also avoids having to defend a fixed level with reserves.