Money Creation and the Bank Multiplier Effect

The Financial System and the Process of Money Creation

Cash represents a very small percentage of the total money circulating in an economy. The mechanism by which the financial system ultimately determines the amount of money in circulation is known in economics textbooks as the bank multiplier.

Understanding the Bank Multiplier and Reserve Ratio

Let's illustrate this process with an example. We start with a small amount of cash, say $1,000. The owner, seeking security or a small interest return, decides to deposit it into a checking account at a bank.

According to banking regulations, the bank only has to keep a small amount of money in its safe, known as the cash ratio (or reserve requirement).

The $1,000 Deposit Example

If the reserve ratio is 10 percent (0.10), the process unfolds as follows:

• The bank only has to keep $100 (10 percent of the initial $1,000) in reserve.
• The bank lends the remaining $900 to someone else.

In this way, the initial $1,000 has automatically generated $1,900 in the money supply ($1,000 principal that you can withdraw at any time, plus the $900 loan).

The borrower uses the $900, and the recipient deposits that money into their checking account. The process repeats:

• The second bank then reserves 10 percent of the $900, which is $90.
• The bank lends the remaining $810.

Thus, the initial $1,000 has resulted in a total money supply of $2,710 ($1,000 + $900 + $810) after only two operations.

The Multiplier Formula and Maximum Monetary Growth

When this process finishes, the initial $1,000 will have ultimately become $10,000. This is a result of the bank multiplier, which is always the inverse of the reserve ratio:

$$\text{Multiplier} = \frac{1}{\text{Reserve Ratio}}$$

In this example: $1 / 0.10 = 10$. Therefore, $1,000 \times 10 = $10,000.

The multiplier represents the maximum potential monetary base growth of an economy. The multiplier effect is a very important variable for central banks to consider, since a small increase in the monetary base results in a much larger growth of the money supply.

System Stability and Fragility

People tend to maintain similar average balances, and payments usually respond to predictable patterns of behavior. Banks rely on this stability to ensure they have sufficient money available at all times to meet withdrawal demands.

The process of generating money in an economy is inherently fragile. Consequently, the financial sector is subject to greater supervision than other sectors, as governments must act immediately when there is a massive loss of confidence in the system (e.g., a bank run or credit crunch).

Bank Balance Sheets: Assets and Liabilities

Deposits and loans are two sides of the same coin. Bank assets are typically decomposed into:

• Loans to individuals and entities resident in the euro area.
• Loans to nonresidents.

On the other side of the balance sheet are liabilities—the financial system's debt to other agents. These liabilities include the monetary aggregates.

Geometric Progression in Banking

This mechanism is based on a geometric progression ratio (1 minus the reserve ratio, or 1 - 0.10). For further understanding of this mathematical concept, consult resources on geometric progressions.