How Does Currency Hedging Affect a Fund's Tracking Difference?
Buying foreign stocks or bonds means taking on two things at once, the investment itself and the currency it’s priced in, and some funds try to strip the second one out.
The short answer
Currency hedging is a strategy funds use to reduce or offset the impact of exchange-rate movements on foreign holdings, typically through contracts like currency forwards. Hedging can make a fund’s return closer to the “local currency” performance of its holdings, but the mechanics of hedging carry their own costs and imperfections, which can cause the fund’s tracking difference from its stated benchmark to be larger or more variable than an unhedged fund’s would be.
Why funds hedge currency exposure at all
When a US-based fund holds foreign securities, its return in dollars depends on both how those securities perform in their local currency and how that currency moves against the dollar. A hedged fund uses financial contracts to offset most of the currency movement, aiming to isolate the underlying investment return. This can appeal to investors who want exposure to foreign companies or bonds without also taking on currency risk as a separate, often unpredictable, variable.
Where the tracking gap comes from
- Hedging costs. Currency forward contracts aren’t free to enter or maintain, and those costs are a drag relative to a benchmark that assumes hedging happens with no friction.
- Interest rate differentials. The cost of hedging is heavily influenced by the difference between interest rates in the two currencies involved, and that differential changes over time, which is set by market conditions and central bank policy rather than anything the fund controls.
- Imperfect hedge ratios. Hedges are often rebalanced periodically, not continuously, so there can be brief windows where the hedge doesn’t perfectly offset currency movement.
- Benchmark construction. If the fund’s actual hedging approach doesn’t precisely match the methodology used to calculate its hedged benchmark, a gap can appear even when the fund is executing its strategy correctly.
How this compares with other sources of tracking gap
Currency hedging is a more specialized contributor to tracking difference than the more universal factors like fees, cash drag, or sampling, since it only applies to funds that hedge in the first place. But where it applies, it can be a meaningful piece of the puzzle, particularly during periods when interest rate differentials between currencies are wide or shifting quickly.
Why hedging effectiveness varies over time
A hedge that worked cleanly in a calm period may perform differently during a stretch of unusual currency volatility or sharp interest rate changes. This variability is one reason funds disclose their hedging methodology and historical tracking record separately, rather than assuming a hedge behaves identically in every market environment.
What to weigh
A currency-hedged fund is trying to solve a specific problem — isolating investment return from currency swings — but that solution introduces its own costs and timing imperfections. Comparing a hedged fund’s actual historical tracking difference against its hedged benchmark, rather than assuming the hedge works perfectly, gives a more complete picture of what the strategy has actually delivered.