Quantity Theory of Money

What is this formula?

The Quantity Theory of Money expresses the relationship between the money supply, the velocity of money, the average price level, and the real output of an economy.

It states that the total money spent in an economy (MV) equals the nominal value of goods and services produced (PQ).

When to use it

Use this formula when analyzing inflation, monetary policy, money supply effects, and macroeconomic equilibrium.

It is commonly used in introductory and intermediate macroeconomics courses and in monetary policy discussions.

Example

Suppose:

Money supply M = 2,000 billion USD

Velocity of money V = 4

Real output Q = 5,000 billion units

Formula:

MV = PQ

Substitution:

P = (M × V) / Q

P = (2000 × 4) / 5000

P = 1.6

Result:

The implied aggregate price level is 1.6.

Applications

- Monetary policy analysis

- Inflation studies

- Central bank modeling

- Economic forecasting

- Macroeconomic education