Inflation and Wealth: Understanding Erosion and Protecting Your Purchasing Power

Your wealth grew 3% this year. Good news? Not necessarily. If inflation was 4%, you actually lost purchasing power. The 3% on your statement is an illusion — your money buys less than it did a year ago.

Nominal performance — the number shown on most bank statements, brokerage accounts and insurance reports — tells an incomplete story. Real performance, adjusted for inflation, tells the truth. And the truth is not always pleasant.

Inflation in 3 minutes

Inflation is the general rise in prices. When inflation is 3%, what cost €100 a year ago costs €103 today. Your groceries, your rent, your energy bill — everything costs a little more, month after month.

The effect is invisible in the moment. Your €10,000 in a savings account remains €10,000. The number does not move. But those €10,000 buy fewer things. It is a silent loss — no notification, no red line on the statement. Just purchasing power slowly eroding.

Recent history is a sharp reminder. In Europe, inflation was negligible between 2015 and 2020 — around 1% per year. Then 2022 arrived: inflation surged to 5–6% in France, over 9% in the UK, and above 8% in the US, driven by energy costs and post-Covid supply chain disruptions. By 2025–2026, it has fallen back toward 2–3%, but the lesson endures: inflation is not a textbook concept. It is an invisible tax on savings.

Nominal vs real return: the essential distinction

Nominal is what you see

The nominal return is the number displayed on your statement. A French Livret A (regulated savings account, tax-free) yields 2.4%. A life insurance contract's fonds euros shows 2.5%. Your MSCI World ETF returned +8% for the year. These figures are correct — but they do not tell you whether your purchasing power improved.

Real is what matters

The real return is the nominal return minus inflation. It is the only metric that measures whether you are genuinely getting wealthier.

Real return ≈ Nominal return − Inflation rate

The numbers that open your eyes

Take a year with 2% inflation — a typical level in 2025–2026:

Current account: 0% nominal − 2% inflation = −2% real. Every year, money sitting in a current account loses 2% of its purchasing power. On €50,000, that is €1,000 lost in a single year — without the balance moving a cent.

Regulated savings (Livret A in France, Cash ISA in the UK, HYSA in the US): 2–4% nominal − 2% = +0 to +2% real. Barely positive. These accounts preserve purchasing power, but only just. They are protection tools, not wealth builders.

Bond funds and fonds euros: 2.5% nominal − 2% inflation − taxes on gains ≈ ~0% real. After tax and inflation, these products maintain capital in real terms — they no longer grow it.

Global equity ETF (MSCI World): +8% nominal − 2% = +6% real. This is where wealth genuinely advances in purchasing power terms. But with short-term volatility that the previous products do not carry.

The trap is clear: a 3% nominal return with 4% inflation is worse than a 1% return with 0% inflation. The first makes you poorer. The second makes you richer. Nominal returns mislead — real returns tell the truth.

How inflation affects each asset type

Cash and savings accounts: the first victims

Current accounts, savings accounts, money market funds — these are hit first. Their returns are fixed or near-fixed, and they only partially compensate for inflation (regulated savings) or not at all (current accounts). This is why the emergency fund is necessary but should not be oversized: beyond the safety net, every extra euro or dollar in cash loses purchasing power.

Bonds and fixed-income: structurally vulnerable

Bond funds, fonds euros in French life insurance, and fixed-rate instruments are structurally vulnerable to inflation. When prices rise, the fixed return does not keep up — or follows with a lag. In 2022–2023, inflation surged to 5%+ while many bond funds and fonds euros were still yielding 1.5–2%. The real return was negative by 3 percentage points.

Real estate: partial protection

Real estate is historically correlated with inflation. In France, rents are indexed to the IRL (Indice de Référence des Loyers). In the UK and US, landlords can adjust rents at lease renewal. Property values tend to follow inflation over long periods. But this is not a perfect hedge: the 2023–2024 corrections showed that property prices can fall even during inflationary periods, especially when interest rates rise sharply. Rental yields should be measured in real terms, not nominal.

Equities and ETFs: the strongest long-term protection

Over the long run, equities outperform inflation. The reason is structural: companies pass price increases through to their revenues and margins. When everything costs more, companies also charge more. Profits follow — and share prices with them.

But this protection only works over time. In the short term, stocks can drop sharply — even during inflation. Diversification reduces risk; it does not eliminate it.

Real estate funds (SCPI): partial indexation

SCPI (French real estate investment trusts) offer some protection through adjustable rents. But high entry fees (8–12%) and limited liquidity temper the advantage. It takes several years of yield to recoup entry costs alone — which limits the ability to react to inflation.

Crypto: the false hedge

The narrative of Bitcoin as an "inflation hedge" is popular but fragile. In practice, the correlation between crypto and inflation is weak. In 2022, inflation surged and Bitcoin lost 65%. Volatility dominates everything else — making crypto a diversification asset, not a protection tool.

The long-term impact of inflation

It is over time that inflation reveals its full destructive force. The compounding effect is devastating, even at moderate levels.

With 2% annual inflation — a level considered normal:

€100,000 today = approximately €82,000 in purchasing power in 10 years. Approximately €67,000 in 20 years. Approximately €55,000 in 30 years.

Without doing anything, your money loses almost half its real value in 30 years. Keeping €50,000 in a current account for 20 years at 2% inflation means losing roughly €16,500 in purchasing power — silently.

This is why "doing nothing" with money is actually a costly decision. Inaction has a price. And that price grows with time.

For those building wealth in their 30s, the horizon is long — 30 to 35 years until retirement. Over that span, cumulative inflation is what separates a portfolio that has doubled on paper from one that has genuinely grown.

This is also what makes wealth projection so important: modelling your net worth over 20 years with and without inflation produces radically different trajectories.

Measuring the real performance of your wealth

Most tools display nominal performance. Net worth "rose" 3%, everything seems fine. But if inflation was 2.5%, the real gain is just 0.5%. The satisfaction is nominal — the enrichment is marginal.

What to do

Compare the growth of your net worth against cumulative inflation over the same period. If your wealth grew 15% over 5 years but cumulative inflation was 12%, the real gain is just 3%. Five years of effort for 3% of real progress — that is information nominal returns alone do not provide.

Regular tracking takes on its full meaning when it incorporates this dimension. The question is not "is my wealth rising?" but "is my wealth rising faster than inflation?"

Protecting yourself without overreacting

Diversification remains the best shield

A portfolio spread across real estate, equities, bonds and cash withstands inflation better than one concentrated in a single asset class. Each responds differently: equities outperform over the long term, real estate offers partial indexation, savings accounts preserve liquidity. It is the overall allocation that protects — not any single miracle asset.

Accept the cost of safety

The emergency fund should stay in savings accounts, even when the real return is low or nil. Safety has a price — and that price is a real return close to zero. That is acceptable. What is not acceptable is keeping €50,000 in savings "just in case" when €15,000 would suffice.

Do not fall for alarmism

Inflation at 2–3% is historically normal in developed economies. Periods of high inflation (5%+) are generally temporary. Central banks — the ECB, the Bank of England, the Federal Reserve — have mandates to keep inflation around 2%. This is not a reason to panic — it is a reason to measure and adjust.

Avoid overreaction

The classic mistake: putting everything into real estate or equities "because they protect against inflation" — without considering liquidity, fees or risk profile. Every wealth decision should be made in the global context, not as a reaction to a single variable. A portfolio built solely against inflation is an unbalanced portfolio.

Conclusion

Inflation is an invisible tax on wealth. Ignoring it means accepting a slow but certain erosion of purchasing power. Accounting for it means measuring the real performance of your holdings, sizing your emergency fund correctly, and building a portfolio that grows in real terms — not just in numbers.

Nominal returns reassure. Real returns inform. And it is information that drives good decisions.