Demand for Money

Why People Hold Money

The demand for money is not about wanting money for its own sake — it is about wanting a certain amount of cash or liquid funds to carry out everyday life. People do not hold money because they like the paper; they hold it because money is the medium through which they make purchases, pay bills, and settle debts. The question the textbook asks is: what determines how much money a person or a household chooses to keep?

Two main forces drive this decision: the need to conduct transactions, and the opportunity cost of holding money instead of interest-bearing assets.

The Transaction Motive: Income Determines Demand

The most obvious reason people want money is to buy things. Every time you buy a cup of tea, pay a bus fare, or purchase groceries, you need money in hand (or in a current account) to complete the transaction. The larger the total value of transactions you plan to make over a given period, the more money you will need to hold on average.

What determines the total value of transactions? Your income. A person with a higher income typically spends more — on more goods, more expensive goods, or both — and therefore needs to carry a larger cash balance to support that spending. The textbook states this clearly: a rise in income leads to a rise in the demand for money. This relationship is straightforward and intuitive. If your monthly salary doubles, you will probably keep more money in your wallet or bank account to handle the increased spending.

The Speculative Motive: Interest Rates Matter

But holding money has a cost. If you keep your savings as cash under the mattress or in a zero-interest current account, you are giving up the interest you could have earned by depositing that money in a savings account or buying a bond. The rate of interest is the price of holding money — it is the income you forgo.

When interest rates are high, the opportunity cost of holding money is large. People become less willing to keep idle cash; they prefer to put their savings into interest-earning deposits or financial assets. As a result, the quantity of money demanded falls. Conversely, when interest rates are low, the cost of holding money is small, and people are more willing to keep larger cash balances.

The textbook puts it this way: at higher interest rates, money demanded comes down. This is the speculative demand for money — the part of money demand that responds to changes in the rate of interest.

The Complete Picture

The demand for money, therefore, depends on two variables:

• Income ($Y$) — a rise in income increases the demand for money.
• Rate of interest ($r$) — a rise in the interest rate decreases the demand for money.

We can write this relationship symbolically as:

where $M^d$ is the nominal quantity of money demanded, $Y$ is nominal income (or real income, depending on context), $r$ is the rate of interest, and $L$ is the liquidity preference function. The function $L$ is increasing in $Y$ and decreasing in $r$. …