What is inflation and how does it affect your money?
Inflation is the sustained rise in the general price level of goods and services, which means your money slowly buys less. A €100 bill today buys less than it did 10 years ago, and it will buy even less 10 years from now. For investors, understanding inflation is not optional.
- Inflation is the generalized rise in prices; ECB target is ~2% per year
- Cash and low-interest deposits lose real purchasing power with positive inflation
- Real return = nominal return − inflation (valid approximation for low inflation)
- Over 20–30 year projections, ignoring inflation completely distorts the result
- Equities and real estate have historically protected better against inflation than cash
What inflation actually means
When inflation runs at 3%, the general price level has risen 3% in a year. What cost €100 now costs €103. Central banks such as the European Central Bank aim for around 2% a year, the level they consider healthy. Too little inflation stalls economic activity; too much destroys purchasing power.
How inflation erodes the value of savings
Imagine €10,000 in a checking account earning nothing with inflation at 3%. After one year it is still €10,000 on paper, but it buys what €9,709 bought a year earlier. After 10 years at 3% inflation, those €10,000 have the purchasing power of about €7,441: cash sitting idle loses nearly 26% of its real value in a decade.
Nominal return vs. real return
Real Return ≈ Nominal Return − Inflation. A fund returning 7% with 3% inflation → real return ≈ 4%. A savings account at 1% with 3% inflation → real return: −2%. You lose purchasing power every year even though the number in your account grows. Always compare real returns when evaluating investments.
Why this matters especially for compound interest
Compound interest amplifies any difference in return over time. If you project €200/month for 30 years at 6%, the nominal result looks great. But if inflation is 3%, your real return is only 3%, and the real value of your future capital will be significantly less than the headline number. That's why the FinSimLab compound interest calculator includes an inflation adjustment.
CPI, core inflation, and how they are measured
The most common measure is the Consumer Price Index (CPI), a basket of goods and services bought by a typical household and tracked every month. Core inflation excludes volatile food and energy prices, giving a cleaner signal of underlying price trends.
In the US, the Federal Reserve targets 2% PCE (Personal Consumption Expenditures) inflation, a slightly different measure that tends to run 0.3–0.4 points below CPI. In the eurozone, the ECB targets 2% HICP (Harmonised Index of Consumer Prices). When inflation runs above target for extended periods, central banks raise interest rates to cool spending, which is why high inflation ends up in higher mortgage rates and tighter credit.
How to protect your portfolio against inflation
Assets that have historically kept pace with or outpaced inflation:
Equities (stocks and index ETFs): Over long periods, company revenues and profits tend to grow with inflation, pushing stock prices up. The S&P 500 has beaten inflation by approximately 7% annually over 50+ years.
Real estate: Property values and rental income generally rise with inflation over time.
Inflation-linked bonds: US Treasury Inflation-Protected Securities (TIPS) or European inflation-linked bonds adjust their principal with the inflation rate, which protects the real return.
Assets that lose to inflation: cash, standard savings accounts with low interest rates, and long-term fixed-rate bonds (their fixed payments lose purchasing power as inflation rises).
Frequently asked questions
What is inflation?
The general rise in prices over time, which means the same money buys less.
How is inflation measured?
With consumer price indices such as the CPI in the US or the HICP in the euro area, which track the price of a basket of goods and services.
What is the difference between nominal and real return?
Nominal is the headline return; real is what is left after inflation.
How can I protect my savings?
Keep only the necessary cash and invest the long-term money in assets that have historically beaten inflation.