Level III Core · Currency Management: An Introduction

Strategic Currency Hedging Decisions and the Minimum-Variance Hedge Ratio

Updated 8 October 2026 · Fact-checked

Strategic currency hedging sets a long-run hedge ratio from the client's IPS. The minimum-variance hedge ratio is the regression slope of the portfolio's domestic-currency return on the foreign-currency return. Passive hedging holds a fixed ratio by rule. Active hedging changes the ratio to try to add return.

Understand Managing Currency Risk: Strategic Hedging Decisions

When you hold foreign assets, your return has two parts: the local asset return and the currency return. Currency moves add volatility. Whether that extra volatility is a problem depends on the asset, the client and the currencies involved.

The investment policy statement (IPS) sets the framework. It states the client's objectives, risk tolerance, constraints and the benchmark. It should say whether currency exposure is hedged, by how much, and whether the manager may deviate from the benchmark hedge ratio. A low-risk-tolerance client with short-horizon liabilities usually wants more hedging. A client with a long horizon and high risk tolerance may accept more currency risk.

The minimum-variance hedge ratio (MVHR) is the hedge ratio that gives the lowest portfolio variance. You find it by regressing the domestic-currency return of the foreign asset on the foreign-currency (exchange rate) return. The slope is the hedge ratio. Think of it as: how much currency exposure should I sell to cancel the part of my risk that moves with the currency?

The result depends on the asset. Foreign bonds have low local volatility, so currency risk dominates their return. Their MVHR is usually close to 100%. Foreign equities are volatile and their local returns can be correlated with the currency, so the MVHR is often well below 100%. Correlation matters: if the foreign currency tends to fall when the foreign equity falls, holding the currency unhedged adds to the risk. If it tends to rise when the equity falls, holding it offsets risk, and less hedging is needed. Note the MVHR is estimated from history, so it is only as good as the data.

Then you choose a management style. Passive hedging keeps a fixed hedge ratio, often the benchmark ratio, and rebalances by rule. It is low cost and has no currency view. Active hedging lets the manager vary the ratio from the benchmark to add return, using forecasts. It brings extra risk and cost, and only makes sense if the manager has skill and the IPS allows it. Because currency hedging often carries a cost or benefit through the forward points, return impact also matters, not only variance.

Key rules to remember

Domestic-currency return of a foreign asset (approximate): R_DC ≈ R_FC + R_FX; R_FC is the asset's return in foreign currency, R_FX is the foreign currency's change against the domestic currency. The exact form is (1 + R_FC)(1 + R_FX) − 1.
Minimum-variance hedge ratio: h* = Cov(R_DC, R_FX) ÷ Var(R_FX); The slope from regressing R_DC on R_FX. Result is the share of the foreign-asset value to hedge (the slope gives the exposure to hedge).
Variance of domestic-currency return: Var(R_DC) = Var(R_FC) + Var(R_FX) + 2 × Cov(R_FC, R_FX); Uses the approximate return relationship. Shows why a positive covariance between asset and currency raises risk.
Unhedged exposure: Unhedged share = 1 − hedge ratio; Use this to size the currency position left open after hedging.

How to solve Managing Currency Risk: Strategic Hedging Decisions questions

Use this order for any strategic hedging question. It keeps your answer tied to the client, which is what the graders reward.

1Read the IPS details: objectives, risk tolerance, horizon, liabilities and any rules on hedging or active management.
2Identify the assets and their currencies. Decide whether local asset risk is low (bonds) or high (equities).
3If data are given, compute or read the hedge ratio: Cov(R_DC, R_FX) ÷ Var(R_FX), or the regression slope.
4Check the correlation between asset and currency returns. State whether currency adds or offsets risk.
5Choose passive or active hedging and justify it by the IPS, the manager's skill and cost.
6Apply the ratio to the exposure to get the hedge amount, and state the unhedged remainder.
7Write a short conclusion that names the client constraint that drives the answer.

Quickest way: Asset type plus client risk shortcut

When to use it: Use it for qualitative questions asking which hedge ratio fits or whether to hedge at all, when no regression output is given.

Foreign bonds: lean toward a high hedge ratio, near full, since currency risk swamps bond volatility.
Foreign equities: expect a lower MVHR, and say it depends on the correlation with the currency.
Low risk tolerance or short horizon: favour more hedging. High risk tolerance and long horizon: allow more exposure.
If the IPS bars active views or the manager shows no skill: pick passive hedging.
State the reason in one sentence tied to the client.

Common mistakes in Managing Currency Risk: Strategic Hedging Decisions

Saying the minimum-variance hedge ratio is always 100%.
Students think hedging removes all currency risk, so more must always be better.
Fix: A 100% hedge removes the currency exposure but is not always the lowest-variance choice. For equities, correlation with the currency can make a lower ratio better.
Regressing the wrong variables, such as the foreign-currency return on the exchange rate.
The slope formula looks familiar, so the inputs get mixed up.
Fix: Regress the domestic-currency return of the asset on the currency return. Use Cov(R_DC, R_FX) ÷ Var(R_FX).
Ignoring the IPS and answering from theory alone.
The technical method feels like the whole answer.
Fix: Open with the client's risk tolerance, horizon and constraints. Then link the hedge decision to them.
Treating passive hedging as 'no hedging'.
The word passive suggests doing nothing.
Fix: Passive hedging holds a fixed, rule-based hedge ratio, such as the benchmark's. It is a defined hedge with no currency forecast.
Choosing active hedging without checking skill, cost and permission.
Students assume more flexibility earns more return.
Fix: Active hedging adds risk and cost. Support it only if the IPS permits and the manager has demonstrated ability.
Forgetting that the MVHR is estimated from past data.
The number looks precise.
Fix: Note that estimates can change over time and should be reviewed, especially if correlations are unstable.

Worked examples

Example 1

A portfolio holds a foreign equity position. Over a sample period, Cov(R_DC, R_FX) = 0.0018 and Var(R_FX) = 0.0040. The position is worth 8,000,000 in domestic currency. Find the minimum-variance hedge ratio and the amount to hedge.

Show the solution

Use h* = Cov(R_DC, R_FX) ÷ Var(R_FX).
h* = 0.0018 ÷ 0.0040 = 0.45.
Hedge amount = 0.45 × 8,000,000 = 3,600,000.
Unhedged amount = 8,000,000 − 3,600,000 = 4,400,000.

Answer: The minimum-variance hedge ratio is 45%. Hedge 3,600,000 of the position and leave 4,400,000 unhedged.

Example 2

A pension fund has a long horizon, a high risk tolerance and an IPS that allows deviation from the benchmark hedge ratio. It holds foreign government bonds and foreign equities. The board asks for a hedging approach. Recommend one and justify it in brief.

Show the solution

Bonds: local volatility is low, so currency risk dominates. Recommend a high hedge ratio, close to the minimum-variance ratio.
Equities: local volatility is high and the currency may be correlated with it. Recommend a lower hedge ratio based on the regression slope.
Style: the IPS permits deviations, but active hedging adds cost and risk and needs a skilled manager. Recommend a passive, rule-based ratio as the core.
Allow a small, limited active band only if the fund can show currency-forecasting skill and accepts the added risk.

Answer: Hedge most of the bond exposure, hedge the equity exposure at the lower regression-based ratio, and run hedging passively as the core. Permit only a limited active band if skill is shown, because the long horizon and high risk tolerance allow some currency risk but do not justify unrewarded risk.

Exam tips

Start every recommendation with the client's risk tolerance, horizon and IPS rules. Then give the technical point.
If asked to calculate, show Cov ÷ Var and the final number. A correct number alone earns full credit on a calculation, but showing the work helps if you slip.
Follow the command word. 'Determine' wants a number. 'Justify' wants a reason tied to the facts. Give only the number of answers requested.
Contrast bonds and equities when asked which needs more hedging. This is a common item-set angle.
For passive versus active, name one cost or risk of active hedging and one condition that would justify it.

Managing Currency Risk: Strategic Hedging Decisions in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Managing Currency Risk: Strategic Hedging Decisions: frequently asked questions

What is the minimum-variance hedge ratio?

It is the hedge ratio that gives the lowest variance of the domestic-currency portfolio return. You estimate it as the slope from regressing the asset's domestic-currency return on the currency return. It equals Cov(R_DC, R_FX) ÷ Var(R_FX).

Why is the hedge ratio for foreign bonds usually higher than for foreign equities?

Bond returns are stable in local terms, so currency moves make up most of their risk. Equity returns are volatile and may be correlated with the currency. That correlation can reduce the variance-minimising hedge.

What is the difference between passive and active currency hedging?

Passive hedging keeps a fixed hedge ratio set by rule, usually the benchmark's, with no currency view. Active hedging varies the ratio from the benchmark to try to earn extra return. It adds cost and risk and needs skill.

How does the IPS affect the hedging decision?

The IPS sets the client's objectives, risk tolerance, horizon and constraints. It also states whether hedging is required and whether the manager may deviate from the benchmark. Your hedge ratio and style must fit these terms.