Exchange Rates and the Balance of Payments

Introduction

students, imagine you are buying a phone made in another country 📱. The price you pay depends not only on the foreign price of the phone, but also on the exchange rate between currencies. This is why exchange rates matter in everyday life, international trade, tourism, and investment. They also help economists understand how money flows between countries. In this lesson, you will learn how exchange rates work, how they affect exports and imports, and how they connect to the balance of payments, one of the most important records in the global economy.

By the end of this lesson, you should be able to:

Explain key exchange rate terms and balance of payments terminology.
Use IB Economics HL reasoning to show how exchange rate changes affect trade and economic performance.
Connect exchange rates and the balance of payments to the wider global economy.
Interpret simple examples and real-world situations using economic logic.

Exchange rates: the price of one currency in terms of another

An exchange rate is the price of one currency expressed in another currency. For example, if $1$ US dollar buys $0.80$ euros, then the exchange rate is $1\text{ USD} = 0.80\text{ EUR}$. Exchange rates matter because they affect the cost of goods, services, travel, and investment across borders 🌍.

There are two broad ways exchange rates can be described:

Appreciation: a currency becomes more valuable relative to another currency. For example, if $1\text{ USD}$ rises from $0.80\text{ EUR}$ to $0.90\text{ EUR}$, the dollar has appreciated.
Depreciation: a currency becomes less valuable relative to another currency. If $1\text{ USD}$ falls from $0.80\text{ EUR}$ to $0.70\text{ EUR}$, the dollar has depreciated.

In many countries, exchange rates are determined in the foreign exchange market by supply and demand. Demand for a currency rises when foreign buyers want to purchase that country’s exports, invest there, or hold its financial assets. Supply of a currency rises when residents buy foreign goods, invest abroad, or send money out of the country.

A change in the exchange rate affects the relative price of exports and imports. If the domestic currency appreciates, exports become more expensive for foreign buyers and imports become cheaper for domestic consumers. If the domestic currency depreciates, exports become cheaper and imports become more expensive.

Example

Suppose a basketball jersey costs $50$ in the United States. If the exchange rate is $1\text{ USD} = 1\text{ CAD}$, a Canadian buyer pays $50\text{ CAD}$. If the dollar appreciates to $1\text{ USD} = 1.20\text{ CAD}$, the same jersey costs $60\text{ CAD}$. That makes the jersey less attractive to Canadian buyers. This is why exchange rates can strongly influence trade flows.

Exchange rates and exports, imports, and competitiveness

Exchange rates affect a country’s international competitiveness, which means how well its goods and services can compete with those from other countries. A depreciating currency usually improves price competitiveness because exports become cheaper to foreign buyers. At the same time, imports become more expensive, which may encourage consumers to buy domestic goods instead.

However, the effect is not always immediate or guaranteed. IB Economics HL often expects you to think carefully about elasticity. If demand for exports and imports is price elastic, then a depreciation is more likely to increase export revenue and reduce import spending. If demand is price inelastic, the effect may be smaller.

This idea can be linked to the Marshall-Lerner condition, which says that a depreciation is likely to improve the current account if the sum of the price elasticities of demand for exports and imports is greater than $1$.

$$|\varepsilon_x| + |\varepsilon_m| > 1$$

Here, $\varepsilon_x$ is the price elasticity of demand for exports and $\varepsilon_m$ is the price elasticity of demand for imports. If this condition is met, the rise in export volumes and fall in import volumes can improve the trade balance over time.

Real-world reasoning

If a country relies heavily on tourism, a weaker currency can make hotels, meals, and activities cheaper for foreign visitors. That can increase tourist arrivals and raise export earnings from services. On the other hand, if a country depends on imported fuel, food, or machinery, depreciation can raise costs and create inflationary pressure 😬.

The balance of payments: recording economic transactions with the rest of the world

The balance of payments is a record of all economic transactions between residents of one country and the rest of the world over a period of time. It helps economists see whether a country is a net lender or net borrower to the rest of the world, and how it is financed.

The balance of payments has two main parts:

The current account
The financial account

Some courses also mention the capital account, but in IB Economics, the current account and financial account are the most important parts.

The current account

The current account includes:

Trade in goods
Trade in services
Primary income, such as interest, profit, and dividends
Secondary income, such as remittances and transfers

The trade balance is calculated as:

$$\text{Trade balance} = \text{Exports of goods and services} - \text{Imports of goods and services}$$

If exports are greater than imports, the country has a current account surplus. If imports are greater than exports, it has a current account deficit.

The financial account

The financial account records financial flows such as:

Foreign direct investment
Portfolio investment
Loans and bank deposits
Purchase of assets across borders

These flows show how a current account deficit or surplus is financed. For example, if a country imports more than it exports, it must attract foreign capital or use reserves to balance the overall accounts.

How exchange rates and the balance of payments are connected

Exchange rates and the balance of payments affect each other. This connection is central to IB Economics HL and the global economy.

If a country has a current account deficit, it is buying more from the rest of the world than it is selling. This usually means there is high demand for foreign currency and lower demand for the domestic currency, which can put downward pressure on the exchange rate. A depreciation may then make exports more competitive and imports more expensive, helping correct the imbalance over time.

At the same time, a change in the exchange rate can itself alter the balance of payments. For example:

A depreciation may improve the current account if export and import volumes respond strongly.
An appreciation may worsen the current account because exports fall and imports rise.
Strong foreign investment inflows can increase demand for the domestic currency and cause it to appreciate.

This means that the balance of payments is not only a record of past transactions. It also helps explain future exchange rate movements and policy choices.

Example of logic in action

Imagine Country A runs a current account deficit because consumers buy lots of imported electronics. Foreigners need the domestic currency to buy Country A’s assets or exports, but demand is not strong enough to offset the demand for foreign currency. The currency may depreciate. As a result, imported electronics become more expensive, reducing import spending over time. This is one way exchange rates can help restore external balance.

Exchange rate systems and policy responses

Countries do not all manage exchange rates in the same way. There are two main systems:

Fixed exchange rate system: the government or central bank maintains the currency at a set value against another currency or a basket of currencies.
Floating exchange rate system: the value of the currency is determined mainly by market forces.

Some countries use a managed float, where the exchange rate is mostly market-determined but the central bank may intervene to reduce extreme movements.

Governments may intervene for several reasons:

To reduce inflation from imported goods
To improve export competitiveness
To protect confidence in the currency
To maintain economic stability

Under a fixed exchange rate, a government may need to buy or sell foreign exchange reserves to keep the rate stable. Under a floating exchange rate, the currency can adjust more freely, which may help the economy absorb shocks.

Why this matters in the global economy

Exchange rates and the balance of payments are part of the wider global economy because they shape trade patterns, capital flows, and living standards. A strong currency can make imports cheaper and help consumers buy foreign goods, but it can hurt exporters. A weak currency can support domestic producers and tourism, but it can also raise the cost of imported essentials.

For developing countries, exchange rate instability can be especially important. A sharp depreciation can increase the cost of imported medicine, fuel, and food. For advanced economies, exchange rates influence multinational firms, financial markets, and trade balances. In both cases, policy makers must consider not just growth, but also sustainability, employment, inflation, and external stability.

students, when you see a news story about a currency falling, think about the full chain of effects: export prices, import prices, inflation, tourism, debt payments, investor confidence, and the current account. That is the kind of connected thinking IB Economics HL values ✅.

Conclusion

Exchange rates are the prices of currencies, and they play a major role in shaping trade, inflation, investment, and competitiveness. The balance of payments records a country’s transactions with the rest of the world and helps show whether it is running a current account surplus or deficit. These two ideas are closely linked: exchange rate changes influence the balance of payments, and balance of payments pressures can influence exchange rates. Together, they help explain how countries interact in the global economy and why governments often pay close attention to external stability.

Study Notes

An exchange rate is the price of one currency in terms of another.
A currency appreciates when it becomes more valuable and depreciates when it becomes less valuable.
A depreciation usually makes exports cheaper and imports more expensive.
The balance of payments records transactions between residents of one country and the rest of the world.
The current account includes goods, services, income, and transfers.
The financial account records cross-border investment and financial flows.
The trade balance is $\text{Exports} - \text{Imports}$.
A current account deficit may create pressure for currency depreciation.
The Marshall-Lerner condition is $|\varepsilon_x| + |\varepsilon_m| > 1$.
Exchange rates affect inflation, competitiveness, tourism, and economic growth.
Fixed, floating, and managed exchange rate systems all have different policy implications.
Exchange rates and the balance of payments are key parts of the global economy.