📚 Foreign Exchange Rates | 汇率
Exchange rates are one of the most important concepts in international economics. Every time a country buys or sells goods across borders, invests overseas, or travels abroad, currencies must be exchanged. Understanding how exchange rates are determined, why they change, and what effects these changes have on an economy is a core requirement of the Cambridge IGCSE Economics syllabus.
汇率是国际经济学中最重要的概念之一。每当一个国家跨境买卖商品、在海外投资或出国旅行时，都需要进行货币兑换。理解汇率如何决定、为何变动以及这些变动对经济产生什么影响，是剑桥IGCSE经济学课程的核心要求。
1. Introduction to Foreign Exchange Rates | 汇率简介
A foreign exchange rate is the price of one currency expressed in terms of another currency. For example, if the exchange rate between the British pound and the US dollar is £1 = $1.30, this means that one pound can be exchanged for one dollar and thirty cents. Exchange rates matter because they affect the price of imports and exports, the profitability of firms that trade internationally, the rate of inflation, and the level of foreign investment.
汇率是一种货币以另一种货币表示的价格。例如，如果英镑与美元之间的汇率是£1 = $1.30，这意味着1英镑可以兑换1美元30美分。汇率之所以重要，是因为它影响进出口商品的价格、国际贸易企业的盈利能力、通货膨胀率以及外国投资的水平。
Exchange rates can be quoted in two ways: the price of one currency in terms of another (for example, £1 = €1.15), or the amount of domestic currency needed to buy one unit of foreign currency (for example, $1 = £0.77). In the IGCSE syllabus, the convention is usually the former: how many units of foreign currency one unit of domestic currency can buy.
汇率有两种报价方式：一种货币以另一种货币表示的价格（例如£1 = €1.15），或者购买一单位外币所需的本币数量（例如$1 = £0.77）。在IGCSE课程中，通常采用前一种惯例：一单位本币可以购买多少单位外币。
2. Exchange Rate Systems | 汇率制度
There are two main types of exchange rate systems: floating and fixed. Under a floating exchange rate system, the value of a currency is determined entirely by the forces of demand and supply in the foreign exchange market, with no government intervention. Under a fixed exchange rate system, the government or central bank sets the value of the currency against another currency or a basket of currencies, and intervenes in the market to maintain that value.
汇率制度主要有两大类：浮动汇率制和固定汇率制。在浮动汇率制度下，货币的价值完全由外汇市场上的供需力量决定，政府不进行干预。在固定汇率制度下，政府或中央银行设定货币对另一种货币或一篮子货币的汇率，并在市场上进行干预以维持该汇率水平。
In practice, many countries operate a managed float (also called a dirty float), where the currency is mostly determined by market forces, but the central bank occasionally buys or sells its currency to influence its value in a desired direction. China, for example, has historically managed the yuan within a narrow band against the US dollar, while the UK and the USA allow the pound and the dollar to float freely.
在实践中，许多国家实行管理浮动汇率制（也称为肮脏浮动），即货币主要由市场力量决定，但中央银行偶尔买卖本国货币以将汇率引导至期望的方向。例如，中国历史上将人民币兑美元的汇率控制在一个狭窄的区间内，而英国和美国则允许英镑和美元自由浮动。
3. How a Floating Exchange Rate Is Determined | 浮动汇率的决定机制
In a floating exchange rate system, the exchange rate is determined by the demand for and the supply of a currency in the foreign exchange market. The demand for a currency arises from foreign individuals, firms, and governments who wish to buy that country’s exports, invest in its firms or property, or hold its currency as a reserve asset. The supply of a currency arises from domestic residents who wish to buy imports, invest overseas, or travel abroad, and therefore need to sell their domestic currency to acquire foreign currency.
在浮动汇率制度下，汇率由外汇市场上对一种货币的需求和供给决定。对该国货币的需求来自希望购买该国出口商品、投资该国企业或房地产、或将其货币作为储备资产持有的外国个人、企业和政府。该国货币的供给来自希望购买进口商品、在海外投资或出国旅游的国内居民，他们需要卖出本币以获得外币。
The exchange rate is determined at the point where the quantity of currency demanded equals the quantity supplied, as shown in the diagram below.
汇率在货币需求量等于供给量的点位上决定，如下图所示。
Exchange rate (price of £ in $) on the vertical axis; Quantity of £ on the horizontal axis; Demand (D) slopes downward; Supply (S) slopes upward; Equilibrium at the intersection of D and S.
纵轴为汇率（以美元表示的英镑价格）；横轴为英镑数量；需求曲线（D）向下倾斜；供给曲线（S）向上倾斜；均衡点位于D与S的交点。
An increase in demand for the currency shifts the demand curve to the right, causing the exchange rate to rise, which is called an appreciation. An increase in supply shifts the supply curve to the right, causing the exchange rate to fall, which is called a depreciation.
对该货币需求的增加使需求曲线向右移动，导致汇率上升，这称为升值。供给的增加使供给曲线向右移动，导致汇率下降，这称为贬值。
4. Causes of Changes in Exchange Rates | 汇率变动的原因
Several factors can cause the demand for or supply of a currency to shift, thereby changing the exchange rate. These factors are examined below.
多种因素会导致对一种货币的需求或供给发生移动，从而改变汇率。下面逐一分析这些因素。
Interest rates: Higher interest rates in a country attract foreign investors who seek higher returns on their savings and investments. These investors need to buy the domestic currency to invest, increasing demand for the currency and causing it to appreciate. Conversely, lower interest rates cause capital to flow out, increasing supply and causing depreciation.
利率：一国较高的利率吸引寻求更高储蓄和投资回报的外国投资者。这些投资者需要购买该国货币进行投资，从而增加了对该货币的需求并使其升值。相反，较低的利率导致资本外流，增加货币供给并导致贬值。
Inflation rates: If a country has a higher inflation rate than its trading partners, its exports become less competitive and its imports become relatively cheaper. This reduces demand for the currency and increases its supply, causing the currency to depreciate. Low inflation tends to strengthen a currency.
通货膨胀率：如果一个国家的通货膨胀率高于其贸易伙伴，其出口商品的竞争力下降，而进口商品相对变得更便宜。这会减少对该货币的需求并增加其供给，导致货币贬值。低通胀往往会使货币走强。
Speculation: Currency traders and financial institutions buy and sell currencies based on their expectations of future exchange rate movements. If traders believe a currency will rise in value, they buy it now to profit later, increasing demand and pushing the exchange rate up. If they expect a fall, they sell the currency, increasing supply and pushing the rate down.
投机行为：外汇交易员和金融机构根据对未来汇率走势的预期买卖货币。如果交易员认为某种货币将会升值，他们现在就会买入以在日后获利，这增加了需求并推高了汇率。如果他们预期贬值，就会卖出该货币，增加供给并压低汇率。
Trade flows: If a country’s exports rise relative to its imports, foreign buyers need more of the domestic currency to pay for those exports, increasing demand and causing appreciation. If imports rise faster than exports, more domestic currency is supplied to buy foreign currency, causing depreciation.
贸易流动：如果一个国家的出口相对于进口增加，外国买家需要更多本币来支付这些出口商品，从而增加需求并导致升值。如果进口增长快于出口，就会有更多本币被供给以购买外币，从而导致贬值。
Government policy: Governments may deliberately change interest rates or directly intervene in the foreign exchange market to influence the exchange rate. This is covered in more detail in Section 7.
政府政策：政府可能有意改变利率或直接干预外汇市场以影响汇率。这将在第7节中详细讨论。
5. Effects of a Depreciation | 贬值的效应
A depreciation means the domestic currency has fallen in value relative to other currencies. This has both positive and negative effects on the economy, as summarised below.
贬值意味着本币相对于其他货币的价值下降。这对经济既有积极影响也有消极影响，总结如下。
Effects on exports and imports: A depreciation makes a country’s exports cheaper for foreign buyers. For example, if the pound depreciates from £1 = $1.30 to £1 = $1.20, a British product priced at £100 now costs $120 instead of $130, making it more attractive to American buyers. At the same time, imports become more expensive for domestic consumers because more pounds are needed to buy the same quantity of foreign currency. This tends to improve the current account balance, provided demand is price-elastic.
对进出口的影响：贬值使一国出口商品对外国买家更便宜。例如，如果英镑从£1 = $1.30贬值至£1 = $1.20，一件定价100英镑的英国商品现在售价为120美元而非130美元，对美国买家更具吸引力。同时，进口商品对国内消费者变得更昂贵，因为购买相同数量的外币需要更多英镑。在需求具有价格弹性的前提下，这往往会改善经常账户余额。
Effects on inflation: Because imports become more expensive, the cost of imported raw materials and components rises, which increases firms’ costs of production. These higher costs are often passed on to consumers in the form of higher prices, leading to cost-push inflation. This is a significant drawback of depreciation.
对通货膨胀的影响：由于进口商品变得更昂贵，进口原材料和零部件的成本上升，从而增加了企业的生产成本。这些更高的成本往往以价格上涨的形式转嫁给消费者，导致成本推动型通货膨胀。这是贬值的一个重大缺点。
Effects on economic growth and employment: The boost to exports can increase demand for domestic goods and services, leading to higher output and employment in export-oriented industries. This can stimulate economic growth. However, if the economy is heavily reliant on imported inputs, the higher cost of these inputs may offset some of the benefits.
对经济增长和就业的影响：出口的提振可以增加对国内商品和服务的需求，从而带动出口导向型产业的产出和就业增长。这可以刺激经济增长。然而，如果经济高度依赖进口投入品，这些投入品成本上升可能会抵消部分收益。
Effects on foreign investment: A depreciation makes a country’s assets, such as property and shares, cheaper for foreign investors, which may attract inward foreign direct investment. However, it also reduces the value of foreign investments held by domestic residents when converted back into domestic currency.
对外国投资的影响：贬值使一国的资产（如房地产和股票）对外国投资者更便宜，这可能会吸引外国直接投资流入。然而，贬值也会减少国内居民持有的外国投资兑换回本币时的价值。
6. Effects of an Appreciation | 升值的效应
An appreciation means the domestic currency has risen in value relative to other currencies. The effects are generally the opposite of those of a depreciation.
升值意味着本币相对于其他货币的价值上升。其效应通常与贬值相反。
Effects on exports and imports: An appreciation makes exports more expensive for foreign buyers, reducing the competitiveness of domestic firms in international markets. Imports, however, become cheaper, benefiting consumers who can buy foreign goods at lower prices. The current account balance tends to worsen if demand is price-elastic, as export volumes fall and import volumes rise.
对进出口的影响：升值使出口商品对外国买家更昂贵，降低了国内企业在国际市场上的竞争力。然而进口商品变得更便宜，消费者能够以更低价格购买外国商品。在需求具有价格弹性的情况下，经常账户余额往往会恶化，因为出口量下降而进口量上升。
Effects on inflation: Cheaper imports reduce the cost of imported inputs and consumer goods, which helps to lower the inflation rate. An appreciation therefore acts as a disinflationary force, helping the central bank keep prices stable.
对通货膨胀的影响：更便宜的进口商品降低了进口投入品和消费品的成本，有助于降低通货膨胀率。因此升值起到抑制通胀的作用，帮助中央银行维持物价稳定。
Effects on economic growth and employment: The fall in export competitiveness may reduce output and employment in export industries and in firms that compete with cheap imports. Consumers benefit from lower prices, so the overall welfare effect is mixed. The government may face pressure to intervene if domestic industries are badly affected.
对经济增长和就业的影响：出口竞争力下降可能会减少出口产业和与廉价进口竞争的企业的产出和就业。消费者从更低的价格中受益，因此整体福利效应是混合的。如果国内产业受到严重影响，政府可能面临干预的压力。
Effects on foreign investment: An appreciation makes foreign assets cheaper for domestic residents, encouraging outward investment. It also makes domestic assets more expensive for foreign investors, which may reduce inward foreign direct investment inflows.
对外国投资的影响：升值使外国资产对国内居民更便宜，鼓励对外投资。同时它也使国内资产对外国投资者更昂贵，可能会减少外国直接投资的流入。
7. Government Intervention in the Forex Market | 政府对外汇市场的干预
Governments and central banks may intervene in the foreign exchange market for several reasons: to maintain a fixed exchange rate, to smooth excessive fluctuations, or to achieve a competitive exchange rate for their exporters.
政府和中央银行可能出于多种原因干预外汇市场：维持固定汇率、平息过度波动，或为出口商实现有竞争力的汇率。
Under a fixed exchange rate system, the central bank stands ready to buy or sell its own currency to maintain the pegged rate. If the currency is under downward pressure, the central bank uses its foreign exchange reserves to buy its own currency, reducing supply and supporting the exchange rate. If the currency is under upward pressure, the central bank sells its own currency and accumulates foreign reserves. To make intervention more effective, the central bank may also raise or lower interest rates to influence capital flows.
在固定汇率制度下，中央银行随时准备买入或卖出本国货币以维持钉住汇率。如果货币面临下行压力，中央银行动用外汇储备买入本币，减少供给以支撑汇率。如果货币面临上行压力，中央银行卖出本币并积累外汇储备。为使干预更加有效，中央银行还可能提高或降低利率以影响资本流动。
Governments can also impose exchange controls, such as limiting the amount of foreign currency that residents can buy, restricting capital outflows, or requiring exporters to convert their foreign earnings into domestic currency. These measures directly reduce the supply of domestic currency in the foreign exchange market, helping to support its value.
政府还可以实施外汇管制，例如限制居民购买外币的金额、限制资本外流，或要求出口商将外汇收入兑换为本币。这些措施直接减少了外汇市场上本币的供给，有助于支撑其价值。
Intervention, however, has costs. Using foreign exchange reserves to support a currency can deplete reserves rapidly if the pressure persists. Raising interest rates to defend a currency can harm domestic investment and growth. Exchange controls can distort trade and create black markets. These costs explain why many countries prefer floating rates.
然而干预是有成本的。如果贬值压力持续，用外汇储备支撑货币会迅速耗尽储备。为捍卫货币而提高利率会损害国内投资和增长。外汇管制会扭曲贸易并催生黑市。这些成本解释了为什么许多国家倾向于浮动汇率。
8. Fixed Exchange Rates: Pros and Cons | 固定汇率制的利弊
Under a fixed exchange rate system, the central bank commits to keeping the exchange rate at a predetermined level. Businesses and individuals have certainty about future currency values, which encourages international trade and investment.
在固定汇率制度下，中央银行承诺将汇率维持在一个预定水平。企业和个人对未来货币价值有确定性预期，这鼓励了国际贸易和投资。
Fixed rates impose discipline on government policy. Because the central bank must maintain reserves and intervene as needed, governments are less able to pursue reckless monetary or fiscal policies that would cause inflation and deplete reserves. This credibility can attract long-term foreign investment.
固定汇率为政府政策带来纪律约束。由于中央银行必须维持储备并按需干预，政府不太可能推行会导致通胀和耗尽储备的鲁莽货币或财政政策。这种可信度可以吸引长期外国投资。
However, maintaining a fixed rate requires large foreign exchange reserves, which can be expensive to hold. A country may also lose control of its domestic monetary policy because interest rates must be set at a level consistent with the exchange rate target, not with domestic economic conditions. If the rate is set at an overvalued level, the currency becomes uncompetitive, exports suffer, and a balance of payments crisis may result.
然而，维持固定汇率需要大量外汇储备，持有成本高昂。一国还可能失去对国内货币政策的控制，因为利率必须设定在与汇率目标一致的水平，而非与国内经济状况一致。如果汇率定在过高水平，货币失去竞争力，出口受损，可能导致国际收支危机。
9. Floating Exchange Rates: Pros and Cons | 浮动汇率制的利弊
Floating exchange rates offer automatic adjustment of the external balance. If a country has a current account deficit, its currency tends to depreciate, which makes exports cheaper and imports dearer, helping to correct the deficit without requiring government action.
浮动汇率制能够自动调整对外收支平衡。如果一国出现经常账户赤字，其货币趋于贬值，这使出口更便宜、进口更昂贵，有助于在不需政府干预的情况下纠正赤字。
Floating rates give policymakers greater freedom to set interest rates according to domestic economic conditions. For example, a central bank can raise interest rates to control inflation without worrying about an exchange rate target. There is no need to maintain large foreign exchange reserves, and speculation tends to be stabilising because traders buy currencies that are undervalued and sell those that are overvalued.
浮动汇率使政策制定者拥有更大的自由，可以根据国内经济状况设定利率。例如，中央银行可以提高利率来控制通胀，而无需担心汇率目标。不需要维持大量外汇储备，投机行为往往起到稳定作用，因为交易员买入被低估的货币、卖出被高估的货币。
On the other hand, floating rates create uncertainty for firms engaged in international trade. A sudden depreciation can increase costs substantially, while a sudden appreciation can erode export profits. Excessive volatility in exchange rates can deter investment and complicate long-term business planning. Some countries therefore adopt managed floats to combine flexibility with a degree of stability.
另一方面，浮动汇率给从事国际贸易的企业带来不确定性。突然贬值会大幅增加成本，而突然升值会侵蚀出口利润。汇率过度波动可能阻碍投资并使长期商业规划复杂化。因此一些国家采用管理浮动，将灵活性与一定程度的稳定性结合起来。
| Feature | Fixed Exchange Rate | Floating Exchange Rate |
|---|---|---|
| Determination | Set by government / central bank | Determined by market demand and supply |
| Certainty | High – businesses know future rates | Low – rates fluctuate continuously |
| Reserves needed | Large reserves required | Minimal reserves required |
| Policy freedom | Limited – interest rates tied to exchange rate target | Full – interest rates used for domestic goals |
| Adjustment | Slow – requires deliberate devaluation or revaluation | Automatic – market forces correct imbalances |
| 特征 | 固定汇率制 | 浮动汇率制 |
|---|---|---|
| 决定方式 | 由政府/中央银行设定 | 由市场供需决定 |
| 确定性 | 高 – 企业知道未来汇率 | 低 – 汇率持续波动 |
| 所需储备 | 需要大量储备 | 几乎不需要储备 |
| 政策自由度 | 有限 – 利率受限于汇率目标 | 充分 – 利率服务于国内目标 |
| 调整机制 | 缓慢 – 需要刻意贬值或升值 | 自动 – 市场力量纠正失衡 |
10. Exam Tips and Key Terms | 考试技巧与关键术语
In Cambridge IGCSE Economics Paper 2, exchange rate questions often appear as part of data response or structured essay questions. You should be able to draw and interpret demand and supply diagrams for a currency, explain how each factor shifts the curves, and evaluate the economic consequences of depreciation and appreciation.
在剑桥IGCSE经济学试卷二中，汇率问题通常出现在数据回应或结构化论文题目中。你应该能够绘制和解读一种货币的供需图，解释每个因素如何移动曲线，并评价贬值和升值的经济后果。
When answering evaluation questions, remember that the effect of an exchange rate change depends on the price elasticity of demand for exports and imports. If demand is elastic, a depreciation will improve the current account; if demand is inelastic, the current account may worsen in the short run (the Marshall-Lerner condition). Time lags also matter, which is why the J-curve effect can occur.
回答评价类问题时，请记住汇率变化的影响取决于进出口需求的价格弹性。如果需求有弹性，贬值将改善经常账户；如果需求缺乏弹性，经常账户短期内可能恶化（马歇尔-勒纳条件）。时滞也很重要，这就是为什么会出现J曲线效应。
Key terms you must be able to define: exchange rate, appreciation, depreciation, revaluation, devaluation, floating exchange rate, fixed exchange rate, managed float, foreign exchange reserves, current account.
你必须能够定义的关键术语：汇率、升值、贬值、法定升值、法定贬值、浮动汇率、固定汇率、管理浮动、外汇储备、经常账户。
Remember that appreciation and depreciation refer to changes in a floating exchange rate caused by market forces, while revaluation and devaluation refer to deliberate changes in a fixed exchange rate made by the government.
请记住，升值和贬值指浮动汇率制度下由市场力量引起的变动，而法定升值和法定贬值指政府在固定汇率制度下刻意调整汇率。
Use one or two well-chosen examples in your answers, such as the pound’s depreciation after the 2016 Brexit referendum, or the Swiss franc’s abrupt appreciation when the central bank removed its currency floor in 2015. Real-world examples impress examiners and demonstrate applied understanding.
在回答中运用一两个精心选择的实例，例如2016年英国脱欧公投后英镑的贬值，或2015年瑞士央行取消汇率下限后瑞郎的突然升值。现实世界的案例能给考官留下深刻印象，并展示应用理解能力。
Finally, practise drawing the exchange rate diagram until you can do it quickly and accurately. Label the axes, curves, and equilibrium clearly, and show the effect of a shift with arrows. A clear diagram can earn full marks for the analysis component of a question.
最后，反复练习绘制汇率图，直到能够快速准确地完成。清晰标注坐标轴、曲线和均衡点，并用箭头表示移动的方向。一幅清晰的图可以让你在问题的分析部分获得满分。
Published by TutorHao | IGCSE Economics Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
屏轩国际教育cambridge primary/secondary checkpoint, cat4, ukiset,ukcat,igcse,alevel,PAT,STEP,MAT, ibdp,ap,ssat,sat,sat2课程辅导，国外大学本科硕士研究生博士课程论文辅导Cancel reply