Welcome to Macroeconomics: The Nature and Functions of Money

Hello! Welcome to one of the most practical chapters in your Business Economics studies. We use money every single day, but have you ever stopped to think about what it actually is? In this section, we will explore why money exists, what makes "good" money, and how we measure it in a modern economy like Hong Kong. Don't worry if economics feels a bit abstract—we'll use plenty of everyday examples to keep things grounded.

1. What is Money?

In simple terms, money is anything that is widely accepted as payment for goods and services or for the repayment of debts. Before money, people used the barter system (trading a bag of rice for a chicken). However, barter is difficult because you need a "double coincidence of wants"—you have to find someone who has what you want and wants exactly what you have!

Quick Review: Money solves the problems of barter by acting as a "go-between" for trade.

2. The Four Functions of Money

To be considered "money," something must perform four specific jobs. A great way to remember these is the mnemonic: "M.U.S.S."

A. Medium of Exchange

This is the most important function. Money allows us to buy and sell goods without trading physical items. Instead of giving a hair stylist a box of apples, you give them $100 HKD. It facilitates trade and specialization.
\nExample: Buying a coffee with a $50 note.

B. Unit of Account (Measure of Value)

Money acts as a "yardstick" to measure the value of different goods. It provides a common language for prices. Without this, we wouldn't know if a car is worth 500 or 5,000 chickens.
Example: Seeing a price tag of $10,000 on a laptop and $5 on a pen allows you to compare their relative value easily.

C. Store of Value

Money allows you to transfer purchasing power from the present to the future. You can earn money today and spend it next month. While inflation can reduce this power, money is generally a safe way to hold wealth because it is highly liquid (easily spent).
Example: Putting $1,000 in a savings account to spend on a holiday next year.

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D. Standard of Deferred Payment

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This means money can be used to settle debts that will be paid in the future. When you take out a loan or buy something on credit, the amount you owe is expressed in money.
\nExample: A student loan that you agree to pay back in monthly installments of $2,000 HKD starting next year.

Key Takeaway: Money must be a medium of exchange, a unit of account, a store of value, and a standard for future payments.

3. Characteristics of "Good" Money

Why do we use gold or paper notes instead of strawberries or heavy rocks? To be effective, money should have these traits:

• Durability: It shouldn't rot or fall apart easily (unlike fruit).
• Portability: It must be easy to carry around (unlike giant boulders).
• Divisibility: It must be able to be broken down into smaller units for small purchases (like cents).
• Scarcity (Limited Supply): If money grew on trees, it wouldn't be valuable. Its supply must be controlled.
• Acceptability: People must be willing to accept it as payment.

4. Defining the Money Supply (The Hong Kong Context)

In your exams, you need to know how the government and economists measure how much money is "out there." In Hong Kong, the Hong Kong Monetary Authority (HKMA) defines money supply in three tiers: M1, M2, and M3.

M1 (The Narrowest Definition)

M1 focuses on liquidity—money that can be spent immediately. It includes:
1. Currency: Notes and coins held by the public.
2. Demand Deposits: Money in current accounts at licensed banks that you can withdraw or spend via debit card instantly.

Formula: \( M1 = \text{Currency held by public} + \text{Demand deposits} \)

M2

M2 is broader. It includes everything in M1, plus items that are slightly less liquid but can be converted to cash fairly quickly.
1. All items in M1.
2. Savings deposits and time deposits (fixed deposits) with licensed banks.
3. Negotiable Certificates of Deposit (NCDs) issued by licensed banks held by the public.

Formula: \( M2 = M1 + \text{Savings/Time Deposits} + \text{NCDs (Licensed Banks)} \)

M3 (The Broadest Definition)

M3 includes everything in M2, plus deposits with other types of financial institutions in Hong Kong.
1. All items in M2.
2. Deposits with Restricted Licence Banks (RLBs) and Deposit-taking Companies (DTCs).
3. NCDs issued by RLBs and DTCs held by the public.

Formula: \( M3 = M2 + \text{Deposits/NCDs with RLBs and DTCs} \)

Common Mistake to Avoid: Students often forget that M2 includes M1, and M3 includes M2. They are like nesting dolls!

5. The Concept of Liquidity

Liquidity refers to how quickly and easily an asset can be turned into cash without losing its value.
• High Liquidity: Cash in your pocket (M1).
• Lower Liquidity: A 1-year fixed deposit or a house (takes time to sell/convert).

Did you know? Even though credit cards are used for shopping, they are not considered part of the money supply. A credit card is a tool to take out a short-term loan; the "money" is actually the bank's payment to the merchant later.

6. Summary and Key Takeaways

• Functions: Money is a medium of exchange, unit of account, store of value, and standard of deferred payment.
• Characteristics: Good money is durable, portable, divisible, scarce, and acceptable.
• M1: Highly liquid (Cash + Demand Deposits).
• M2: M1 + Savings/Time deposits at licensed banks.
• M3: M2 + Deposits at Restricted Licence Banks and Deposit-taking Companies.

Don't worry if the M1/M2/M3 distinctions feel a bit technical at first. Just remember that we move from the most "spendable" (M1) to the "least spendable" (M3) forms of money. You've got this!