Skip to content
Moneyplain
All lessons

2.1Making money grow

Inflation: the quiet tax

Cash under the mattress loses value every year. Understanding why is the first step to beating it.

Lesson
5 of 11
Reading
6 min
Module
2 · Making money grow
Updated

Here is a strange fact: you can do everything "right" — work hard, spend less than you earn, keep money in savings — and still get poorer in real terms. The reason is inflation.

What inflation actually is

Inflation is the rate at which the average price of goods and services rises. When people say "inflation is 6% this year," they mean a basket of typical things — food, rent, transport, healthcare — costs about 6% more than a year ago.

It doesn't hit everything equally. Some years rent spikes while electronics get cheaper. But over time, the direction is consistent: prices rise, and each unit of money buys less.

The Rule of 72

A quick mental tool: divide 72 by the inflation rate to find roughly how long it takes prices to double.

  • At 3% inflation: 72 ÷ 3 = 24 years for prices to double.
  • At 6% inflation: 72 ÷ 6 = 12 years.

That second number is why inflation is sometimes called the quiet tax. In 12 years at 6%, $100 of today's purchases will cost about $200.

Nominal vs real: the only comparison that matters

Numbers on a statement are nominal — the face value. What they can actually buy is real. Inflation is the bridge between them.

An easy approximation: real return ≈ your return − inflation.

ScenarioNominal returnInflationReal return
Cash in a drawer0%5%−5%
Savings account3%5%−2%
Government bond6%5%+1%
Broad stock fund (long run, illustrative)8–9%5%+3–4%

The first two rows are losses, even though nothing "went down." That's the invisible part: inflation doesn't send you a statement.

What tends to beat inflation

Long-term, inflation is fought by owning things that produce value or income:

  • Stocks (and broad index funds) — you own a slice of businesses that can raise prices and grow. Historically the strongest long-run inflation fighter, with plenty of scary drops along the way.
  • Real estate and REITs — rents and property values tend to rise with prices, though property is slow to sell.
  • Bonds — usually pay a fixed rate; they beat inflation when the rate is above it, and lose when it isn't.
  • Gold and commodities — often move with inflation over long periods, but pay no income and can be flat for a decade.

The important part is not finding a perfect inflation-proof asset. It's avoiding the default outcome — leaving long-term money idle in cash and slowly losing ground.

Quick check

Your savings account pays 3% while inflation runs at 5%. What is happening to your buying power?

Key takeaways

  1. 01Inflation is the rising average price level; it makes every unit of money buy less.
  2. 02The Rule of 72 estimates how fast prices double at a given inflation rate.
  3. 03Compare real returns (after inflation), not just nominal ones.
  4. 04Cash is for safety and short-term needs; long-term money needs assets that can outpace inflation.

Finished this lesson?

Mark it read to track progress on this device. Nothing is uploaded.