Understanding exchange rates and currency values

Exchange rates play a key role in international trade by determining how much one country's currency is worth compared to another's. These rates are set in the foreign exchange market, where buyers and sellers trade currencies, influencing the flow of goods, services, and financial capital between countries.

Key definitions in the foreign exchange market

• Exchange rate - The price of one currency in terms of another, such as how many euros can be bought with one US dollar.
• Appreciation - An increase in the value of a currency relative to another, meaning it can buy more of the foreign currency.
• Depreciation - A decrease in the value of a currency relative to another, meaning it can buy less of the foreign currency.
• Net exports - The difference between a country's exports (goods and services sold abroad) and imports (goods and services bought from abroad), calculated as exports minus imports.
• Aggregate demand (AD) - The total demand for goods and services in an economy at a given price level, which includes consumption, investment, government spending, and net exports.

These concepts connect because changes in exchange rates affect the competitiveness of a country's goods abroad and the cost of foreign goods at home, ultimately shifting net exports and aggregate demand.

Effects of currency appreciation on net exports

When a currency appreciates, it becomes stronger against other currencies. This change makes a country's goods more expensive for foreign buyers while making foreign goods cheaper for domestic buyers. As a result, the balance of trade shifts in a specific way.

How appreciation impacts exports and imports

• Decrease in exports - Domestic goods become more expensive in foreign markets because foreign buyers need more of their own currency to purchase them. This reduces demand for exports, leading to fewer sales abroad.
• Increase in imports - Foreign goods become cheaper in the domestic market since the stronger currency buys more foreign currency. This boosts demand for imports as consumers and businesses find them more affordable.

Outcome for net exports

The combination of falling exports and rising imports leads to a decrease in net exports. For example, if the US dollar appreciates against the euro, American cars become pricier in Europe, reducing US exports, while European wines become cheaper in the US, increasing imports.

This shift can be illustrated on a graph of net exports against the exchange rate, where an upward shift in the exchange rate (appreciation) moves the net exports curve leftward, showing a lower quantity of net exports at any given level.

Effects of currency depreciation on net exports

Currency depreciation occurs when a currency weakens against others, making it less valuable. This reversal from appreciation alters trade dynamics by adjusting relative prices in the opposite direction.

How depreciation impacts exports and imports

• Increase in exports - Domestic goods become cheaper for foreign buyers because they need less of their own currency to purchase them. This raises demand for exports, encouraging more sales abroad.
• Decrease in imports - Foreign goods become more expensive in the domestic market as the weaker currency buys less foreign currency. This lowers demand for imports, prompting consumers and businesses to seek domestic alternatives.

Outcome for net exports

With exports rising and imports falling, net exports increase overall. For instance, if the US dollar depreciates against the euro, American electronics become more affordable in Europe, boosting US exports, while European machinery becomes costlier in the US, reducing imports.

Graphically, depreciation shifts the net exports curve rightward on a net exports versus exchange rate graph, indicating a higher quantity of net exports at any given level.

How changes in net exports influence aggregate demand

Net exports form one component of aggregate demand, so shifts in net exports directly affect the overall demand in an economy. This connection links currency value changes to broader economic outcomes like output, employment, and price levels.

Effects of net export changes on aggregate demand

• Decrease in net exports (from appreciation) - Reduces aggregate demand because fewer exports mean less foreign spending on domestic goods, and more imports divert domestic spending abroad. This can lead to lower output, higher unemployment, and downward pressure on price levels.
• Increase in net exports (from depreciation) - Boosts aggregate demand as more exports bring in foreign spending, and fewer imports keep more domestic spending at home. This tends to increase output, reduce unemployment, and exert upward pressure on price levels.

Illustrating the impact with graphs

An aggregate demand curve shows these effects: a decrease in net exports shifts the AD curve leftward, while an increase shifts it rightward. Factors causing appreciation or depreciation, such as interest rate changes or inflation differences, initiate these shifts, demonstrating how the foreign exchange market influences the domestic economy.