A currency movement is a single number that lands on two groups of companies in opposite directions. The size and timing of the effect depend on structure rather than on the move itself.
Two sides of the same exchange rate
A weaker home currency makes exports cheaper to foreign buyers and imports dearer to domestic ones. Both statements describe the same rate from different positions.
Exporters convert foreign sales into more home currency, which lifts reported revenue without any change in volume. Importers pay more home currency for the same goods.
Share prices for the two groups therefore separate after a sustained move. Analysts often model this exposure explicitly because it is one of the more predictable relationships in equity markets.
Why exporters gain slowly rather than instantly
Export contracts are typically priced months in advance and frequently denominated in a major international currency. The old rate stays in force until those contracts roll.
Volume gains take longer still, since buyers must renegotiate supply arrangements and qualify new sources. A price advantage translates into orders over quarters, not weeks.
Exporters that import raw materials capture only the net benefit. A firm assembling imported components sees much of the revenue gain consumed by input costs.
How importers absorb the hit
Importers can raise prices, accept thinner margins or reformulate what they sell. Which route they take depends on competition and on how much of the market faces the same pressure.
Where all competitors import, prices tend to rise together. Where domestic substitutes exist, importers absorb more of the cost to hold share.
Retailers with long supply chains face the added problem of timing. Goods on the water were bought at the old rate, so the cost increase arrives one shipment cycle after the currency moved.
Hedging delays the effect on reported profit
Many firms hedge foreign currency exposures for a rolling period ahead. Reported results therefore reflect rates locked in earlier rather than current market levels.
A hedge postpones rather than removes the effect. When it expires, the accumulated move arrives at once, which can make a subsequent quarter look abruptly worse or better.
Disclosure of hedging policy is uneven between companies and between reporting regimes. Two firms with identical exposure can present very different-looking results depending on how far ahead each hedges.
Why a domestic-only firm is not immune
Companies selling entirely at home still buy imported energy, packaging and machinery. Their costs move with the exchange rate even though their revenue does not.
Currency moves also alter central bank behaviour, since a weaker currency raises imported prices. The resulting change in interest rates reaches every listed company regardless of trade exposure.
Competition provides a further channel. A weaker currency makes imported rivals more expensive, so a purely domestic producer may gain pricing room it did nothing to earn.