What Is Inflation and How Does It Affect Your Money?

Inflation is one of those economic terms everyone has an intuitive sense of — prices go up — but understanding the mechanics behind it makes it much easier to follow financial news and market behavior.

The Basic Definition

Inflation is the rate at which the general price level of goods and services rises over time, which correspondingly reduces the purchasing power of a given amount of money. If inflation is running at a certain percentage per year, the same amount of money buys a little less than it did the year before.

What Typically Drives Inflation

Demand-pull inflation — occurs when demand for goods and services outpaces supply, pushing prices upward
Cost-push inflation — occurs when the cost of producing goods rises (like raw materials or wages), and businesses pass those higher costs on to consumers
Monetary factors — when the money supply grows faster than the economy's output of goods and services, each unit of currency tends to be worth relatively less

How Inflation Is Measured

Most countries track inflation using a consumer price index (CPI), which measures the average price change of a fixed basket of goods and services over time — things like food, housing, energy, and transportation.

Why Central Banks Care So Much

Central banks, like the European Central Bank or the US Federal Reserve, typically aim for a moderate, stable level of inflation, since both very high inflation (eroding purchasing power quickly) and deflation (falling prices, which can discourage spending and investment) create economic problems. Interest rate decisions are one of the primary tools central banks use to try to keep inflation within a target range.

How Inflation Affects Markets

Inflation influences markets in several ways: it affects central bank interest rate decisions, which in turn affect borrowing costs and corporate profitability; it erodes the real value of cash sitting idle; and it changes the relative appeal of different asset classes, since some investments tend to hold up better during high-inflation periods than others.

The Takeaway

Inflation measures how quickly your money's purchasing power erodes over time, driven by a mix of demand, supply costs, and monetary factors. Understanding it helps explain a huge share of central bank policy and market behavior that might otherwise seem disconnected from everyday life.