International Trade & Exchange Rates
Why Countries Trade
No country produces everything its people want. The UK cannot grow coffee, mine significant quantities of oil, or manufacture every component inside a smartphone — so it buys these from other countries. At the same time, the UK sells financial services, pharmaceuticals, aerospace equipment and creative content to the rest of the world. This two-way flow of goods and services is international trade.
Countries trade because of comparative advantage: a country should focus on producing goods where its relative opportunity cost is lowest, rather than the goods it simply makes cheapest in absolute terms. Even if one country is more efficient at producing everything, trade still benefits both sides, because each can concentrate on what it does at the lowest relative cost. Countries then export these specialised goods and import those where a trading partner has the comparative advantage — and both end up with more than if they each tried to be self-sufficient.
The UK’s main exports include financial and professional services, pharmaceuticals, aerospace and motor vehicles. Its main imports include manufactured goods, fuels, foodstuffs and electronic components. The UK typically imports more goods than it exports — running a deficit on trade in goods — but earns a surplus on trade in services.
Imports, Exports and the Balance of Trade
Exports bring money into an economy: when a UK car manufacturer sells vehicles to Germany, foreign currency flows into the UK. Imports send money out: when a UK consumer buys an American streaming subscription or a Japanese games console, pounds leave the UK economy. The difference between the value of exports and the value of imports is the balance of trade.
If exports exceed imports, the country has a trade surplus. If imports exceed exports, it has a trade deficit. A persistent deficit can be a concern for the government: it means the country is spending more on foreign goods than it earns from selling abroad, which may put downward pressure on the currency and affect domestic jobs in industries that compete with cheap imports.
Imagine the UK earns £500 billion from exports in a year but spends £600 billion on imports. That £100 billion shortfall is a trade deficit. To fill the gap, the UK must attract foreign money in other ways — for example, by selling assets, borrowing from abroad, or earning income from overseas investments. A surplus country (say, Germany from its car and machine exports) takes in more than it pays out, building up foreign currency reserves or overseas investments. Neither position is automatically good or bad: a deficit can reflect a strong consumer economy, while a surplus can reflect weak domestic demand.
What Is an Exchange Rate?
To trade internationally you need to convert currencies. An exchange rate is simply the price of one currency in terms of another. For example, if the exchange rate between the pound and the dollar is £1 = $1.25, you can swap one pound for one dollar and twenty-five cents. Exchange rates change constantly because they are determined by the demand for and supply of currencies on the foreign exchange market, which operates twenty-four hours a day.
Two acronyms help you remember the effects of exchange rate changes. SPICED: a Strong Pound makes Imports Cheap but Exports Dear (harder to sell abroad). WPIDEC: a Weak Pound makes Imports Dear but Exports Cheap (easier to sell abroad). Learning both acronyms together prevents mixing them up.
How Exchange Rates Are Determined
Think of currency like any other good: if demand for pounds rises, the price of pounds (the exchange rate) rises too. Demand for pounds increases when foreigners want to buy British goods and services, invest in UK assets, or benefit from higher UK interest rates. Supply of pounds increases when UK residents want to buy foreign goods or invest overseas — they sell pounds to get other currencies.
When demand for the pound rises relative to its supply — perhaps because the Bank of England raises interest rates, attracting foreign investors who must first buy pounds — the exchange rate rises. This is called appreciation. When demand falls or supply rises, the exchange rate falls. This is called depreciation.
To picture appreciation: imagine a demand and supply diagram for pounds. The horizontal axis shows the quantity of pounds traded; the vertical axis shows the exchange rate expressed as dollars per pound ($/£) — how many dollars one pound buys. If UK interest rates rise, demand for pounds shifts to the right. The new equilibrium exchange rate is higher — the pound has appreciated. The opposite shift (demand falling) gives a lower equilibrium — depreciation.
Students frequently confuse appreciation and depreciation. A simple check: if £1 buys more dollars today than yesterday, the pound has appreciated (gone up in value). If £1 buys fewer dollars, it has depreciated (gone down). Appreciation and depreciation are the terms used when exchange rates are set by the market. The equivalent terms when a government pegs its currency and adjusts it deliberately are revaluation (up) and devaluation (down) — you may encounter these in extended-answer questions.
Effects of Exchange Rate Changes on Exporters, Importers and Consumers
Exchange rate changes ripple through the economy in predictable chains. Work through SPICED and WPIDEC for each scenario.
The pound appreciates (rises in value): a UK exporter selling machinery priced in pounds suddenly looks more expensive to a foreign buyer who must convert their currency into pounds. Demand for UK exports may fall — particularly if the exporter’s goods are price-elastic. UK importers benefit: foreign goods cost fewer pounds to buy, so UK firms importing raw materials or components face lower costs. Consumers see cheaper foreign goods on the shelves, which keeps inflation down. However, domestic industries facing cheaper foreign competition may lose sales and jobs.
The pound depreciates (falls in value): exports become cheaper for foreign buyers, which can boost demand for British goods and help UK firms win market share abroad. This follows the chain: depreciation → lower export prices in foreign currency → higher foreign demand → more UK production → possible jobs boost. The downside is that imports become more expensive. Raw material costs for UK manufacturers rise, pushing up the cost of production. Consumers face higher prices for imported food, fuel and electronics — feeding through to inflation. The Bank of England watches currency movements closely because a sharp depreciation can push inflation above its 2% target.