HookThe night the pound fell off a cliff
At about 4am on 24 June 2016, as the Leave result in the EU referendum became clear, the pound fell from around $1.50 to $1.33 — its steepest one-day drop in modern history. It was a single currency move that touched every idea in this section at once: a country renegotiating its place in the global economy, the terms on which it trades, the money flowing across its borders, and the exchange rate that prices it all. When the UK finally left the single market and customs union on 1 January 2021, new checks, paperwork and rules of origin raised the cost of trading with Britain's largest partner overnight.
This section is the outward-facing half of macroeconomics. It asks why countries trade at all, how deeply the world economy has knitted together, what the record of a country's international transactions looks like, how currencies are priced, and why some nations grow rich while others stay poor. Brexit is the thread because it forced Britain to confront, in real numbers, questions it had taken for granted for forty years.
ModelGlobalisation
Globalisation is the deepening integration of national economies through trade, investment, migration and the flow of technology and ideas. It is not new, but its modern surge has clear drivers: containerisation and cheaper transport, the trade liberalisation policed by the World Trade Organisation, the internet and instant communication, the deregulation of capital markets, and the rise of transnational corporations that spread supply chains across dozens of countries — an iPhone is designed in California, made from parts across Asia, assembled in China.
The consequences cut both ways, and AQA rewards balance. On the gains side, globalisation helped lift more than a billion people out of extreme poverty since 1990, as the world's poverty rate fell from over a third to under a tenth of the population, and it gives consumers cheaper, wider choice. On the losses side, it exposed Western manufacturing workers to low-cost competition — the so-called 'China shock' hollowed out industrial towns, including many in the UK's North and Midlands — widened some inequalities, and made economies more vulnerable to shocks transmitted through global supply chains, as 2020–21 made painfully clear. Since around 2016, trade has grown more slowly than output, prompting talk of 'slowbalisation' and even reversal.
ModelTrade and comparative advantage
The theoretical case for trade rests on comparative advantage, David Ricardo's insight that a country gains by specialising in what it produces at the lowest opportunity cost, even if another country is better at making everything. This is the distinction from absolute advantage (simply producing more with the same resources): comparative advantage is about relative, not absolute, efficiency, and it is why trade can benefit both a rich and a poor country simultaneously.
Against the gains from specialisation sit the arguments for protectionism. Governments restrict trade using tariffs (taxes on imports), quotas (quantity limits), subsidies to domestic producers, and non-tariff barriers such as regulations and standards — the frictions that Brexit reintroduced with the EU. The classic justifications are protecting infant industries until they can compete, retaliating against dumping (goods sold below cost), safeguarding strategic industries, and defending jobs. The classic counters are higher prices for consumers, retaliation and trade wars, and the risk of propping up permanently inefficient firms. AQA also expects the vocabulary of integration — a free trade area, a customs union with a common external tariff, and a single market with free movement of goods, services, capital and labour, the arrangement Britain left — plus the terms of trade, the ratio of export to import prices.
Two countries, each with a fixed workforce. In a day, a UK worker can produce 10 units of financial services OR 5 units of textiles; a Vietnamese worker can produce 2 units of financial services OR 4 units of textiles. Vietnam has an absolute disadvantage in both. But look at opportunity cost: for the UK, one unit of financial services costs 5 ÷ 10 = 0.5 textiles, while for Vietnam it costs 4 ÷ 2 = 2 textiles. The UK gives up less to make financial services, so it holds the comparative advantage there; by the same logic Vietnam's comparative advantage is in textiles (0.5 financial-service units per textile versus the UK's 2). Each specialises, they trade, and total output rises — which is exactly why the UK runs a services surplus and imports manufactured goods.
ModelThe balance of payments
The balance of payments records every transaction between UK residents and the rest of the world. Its most examined part is the current account, which has four elements: trade in goods, trade in services, primary income (interest, profits and dividends on overseas investments), and secondary income (transfers such as aid and EU-era contributions). A current account deficit means the country is, on these flows, spending more abroad than it earns — importing more than it exports, broadly.
Britain is the textbook chronic-deficit economy: it has run a current account deficit almost every year since the mid-1980s, typically around 3–4% of GDP, driven by a large deficit in goods that a world-leading surplus in services — the City's finance, plus law, education and consulting — only partly offsets. A deficit is not automatically a crisis: it must be financed by matching inflows on the financial account (foreigners buying UK assets, from government bonds to London property), so a current account deficit is the mirror image of a capital inflow. The danger comes if those inflows are volatile 'hot money' that could reverse, or if the deficit signals deep uncompetitiveness rather than attractive investment opportunities.
MechanismExchange rate systems
An exchange rate is the price of one currency in terms of another, and AQA wants you to know the three regimes. Under a floating system, like the pound today, the rate is set by supply and demand in the foreign exchange market: demand for exports and inflows of investment lift a currency, demand for imports and outflows push it down. Under a fixed system the central bank pegs the rate and defends it using reserves and interest rates. A managed float sits between, floating freely but with occasional intervention.
Use the right words: a market-driven rise is an appreciation and a fall a depreciation, whereas a deliberate change to a fixed rate is a revaluation or devaluation. Britain learned the cost of defending a peg on Black Wednesday, 16 September 1992, when it was forced out of the Exchange Rate Mechanism after burning through reserves trying to prop up sterling — the pound has floated ever since. A weaker currency should, in theory, boost net exports by making exports cheaper and imports dearer, but only if demand is elastic enough — the Marshall–Lerner condition — and even then the improvement lags behind the fall, the J-curve effect, because volumes take time to respond while import bills rise immediately.
CaseEconomic growth and development
The section closes by separating two ideas students routinely merge. Economic growth is a rise in real output; economic development is a broader, welfare-focused improvement in living standards — health, education, freedom and opportunity, not just income. Growth can occur without development if the gains are captured by a narrow elite or come at heavy environmental cost. The standard yardstick is the UN's Human Development Index, which blends income per head with life expectancy and years of schooling precisely because GDP alone misses so much.
Development economists study why poorer countries stay poor. Barriers include primary product dependency (reliance on volatile commodity exports), the savings gap that leaves too little for investment (the Harrod–Domar idea), crippling debt, weak institutions and corruption, and poor infrastructure and human capital. Strategies to break out span the market-versus-state divide familiar from supply-side policy: attracting foreign direct investment and expanding trade, targeted aid and debt relief, microfinance, developing tourism, industrialising, and investing in education and health. The record is genuinely mixed — China and, more recently, India have grown fast enough to transform hundreds of millions of lives, while much of sub-Saharan Africa has struggled against exactly the barriers above. The examiner's reward goes to answers that treat development as multidimensional and judge each strategy against a country's specific constraints.
VocabularyKey terms the mark scheme pays for
TrapsMisconceptions that cost marks
ExamWhat examiners want
Comparative advantage is the calculation AQA returns to: set out output per worker, compute opportunity costs by dividing, and identify who gives up least of the other good. Always finish by stating who specialises in what and noting the gain from trade — the interpretation, not just the numbers, earns the marks. Do not confuse it with absolute advantage.
On the balance of payments, name the components of the current account and remember the accounting identity — a current account deficit is mirrored by a financial account surplus, so 'the deficit is financed by capital inflows' is a Level 3 sentence. Evaluate deficits by sustainability and cause, not by assuming a deficit is a failure.
Exchange-rate answers should use the correct term (appreciation/depreciation for floating rates, revaluation/devaluation for fixed) and, on effects, deploy the Marshall–Lerner condition and the J-curve rather than assuming a cheaper pound instantly boosts net exports — Black Wednesday 1992 is your ready-made evaluation of the cost of defending a peg. For development, distinguish growth from development explicitly, reach for the HDI, and judge each strategy against a country's actual constraints. Across the whole section, AQA's top level descriptors demand real, dated context — Brexit, the China shock, the UK's services surplus, Black Wednesday — so weave it in rather than writing in the abstract.