Welcome to the World of Exchange Rates!
Ever wondered why the price of a video game or a pair of sneakers changes when you buy them from another country? Or why your parents wait for the "right time" to change money before a holiday? It all comes down to exchange rates.
In this chapter, we are going to look at money as if it were a product—like a chocolate bar or a phone—that has its own price. Don't worry if it sounds a bit strange at first; by the end of these notes, you’ll be an expert at understanding how the global "price of money" affects everything from the bread in your toaster to the job market!
1. What is an Exchange Rate?
An exchange rate is simply the price of one currency expressed in terms of another currency.
Example: If the exchange rate is \(£1 = \$1.20\), it means you need 1.20 US Dollars to buy just 1 British Pound.
Quick Prerequisite Check: What is Currency?
Currency is the specific type of money used by a country (like the Yen in Japan or the Rupee in India). When countries trade with each other, they usually need to pay in the local currency, which is why we need to "exchange" them.
Key Takeaway: Think of an exchange rate as a "price tag" for money.
2. How is a Floating Exchange Rate Determined?
In the Cambridge syllabus, we focus on a floating exchange rate. This is a system where the value of the currency is decided by the free market—specifically by demand and supply—without the government interfering.
The Demand for a Currency
People "demand" (want to buy) a currency when they want to buy things from that country. This includes:
• Exports: Foreigners needing the local currency to buy the country's goods.
• Foreign Direct Investment (FDI): Foreign firms building factories in that country.
• Speculation: People buying the currency because they think its value will go up later.
The Supply of a Currency
The "supply" of a currency increases when locals want to sell their own money to buy things from abroad. This includes:
• Imports: Locals selling their currency to buy foreign goods.
• Outward Investment: Local firms building factories in other countries.
The Equilibrium: Just like in a normal market, the exchange rate is where the Demand (D) curve and Supply (S) curve for the currency meet. If demand goes up, the price goes up!
3. Up or Down? Appreciation vs. Depreciation
Because the market is always moving, the value of a currency changes constantly. We use two special words to describe this:
1. Appreciation: This is when the value of a currency increases. You can now buy more of a foreign currency than before.
Example: If the rate moves from \(£1 = \$1.20\) to \(£1 = \$1.30\), the Pound has appreciated.
2. Depreciation: This is when the value of a currency falls. You can now buy less of a foreign currency.
Example: If the rate moves from \(£1 = \$1.20\) to \(£1 = \$1.10\), the Pound has depreciated.
Memory Aid: The "A" and "D" Trick
• Appreciation = Adding value (Going Up!)
• Depreciation = Down in value (Going Down!)
Quick Review Box:
• Value goes up = Appreciation
• Value goes down = Depreciation
• Determined by = Demand and Supply
4. Why do Exchange Rates Change?
If the exchange rate is a seesaw, what makes it tilt? Here are the main causes of shifts in demand and supply:
A. Interest Rates (The "Hot Money" Effect)
This is a favorite topic for examiners! If a country increases its interest rates, foreign investors will want to save their money in that country's banks to get higher returns. To do this, they must buy the local currency.
• High Interest Rates \(\rightarrow\) High Demand for Currency \(\rightarrow\) Appreciation.
B. Inflation Rates
If a country has high inflation, its goods become more expensive. Foreigners won't want to buy them (Demand falls), and locals will prefer to buy cheaper imports (Supply of local currency increases as they sell it to buy foreign goods).
• High Inflation \(\rightarrow\) Depreciation.
C. Demand for Exports and Imports
If a country’s products (like Swiss watches or German cars) become very popular, the demand for their currency will rise.
• Popular Exports \(\rightarrow\) High Demand \(\rightarrow\) Appreciation.
D. Speculation
If traders believe a currency will be worth more in the future, they buy it now. This sudden increase in demand causes the currency to appreciate immediately!
Common Mistake to Avoid: Don't confuse "Interest Rates" with "Exchange Rates." Interest rates are the cost of borrowing; exchange rates are the price of currency. However, as we saw above, interest rates influence exchange rates!
5. Impact of Exchange Rate Changes on the Economy
When a currency moves, it sends ripples through the whole economy. We use AD/AS analysis to see the results. To remember the effect of an appreciation (a stronger currency), use the famous SPICED mnemonic:
Strong
Pound
Imports
Cheap
Exports
Dear (Expensive)
How this affects Aggregate Demand (AD)
Recall the formula: \(AD = C + I + G + (X - M)\)
Where \(X\) is Exports and \(M\) is Imports.
If the currency Appreciates:
1. Exports become more expensive for foreigners to buy, so \(X\) falls.
2. Imports become cheaper for locals, so \(M\) rises.
3. Since \((X - M)\) is getting smaller, Aggregate Demand (AD) shifts to the left.
The Consequences of Appreciation:
• Real Output: Decreases (because AD is lower).
• Employment: May decrease (as export firms need fewer workers).
• Inflation: Decreases (this is a good way to "cool down" an overheating economy). Cheap imports also keep prices low.
If the currency Depreciates:
The opposite happens! Exports are now cheap (WIDEC: Weak Currency Imports Dear Exports Cheap).
1. \(X\) rises and \(M\) falls.
2. AD shifts to the right.
3. Real Output increases, Employment increases, but Inflation may rise because imports (like oil) are now more expensive.
Key Takeaway Summary:
• Appreciation: Curbs inflation but can hurt economic growth and jobs.
• Depreciation: Boosts growth and jobs but can lead to higher inflation.
Final Encouragement
Exchange rates can feel like they involve a lot of moving parts. Just remember: it’s all about Demand and Supply. If you can explain why people want to buy or sell a currency, you can figure out the rest! Keep practicing the SPICED mnemonic, and you’ll be ready for any question the exam throws at you.