How Compound Interest Actually Works in Your Favour

Compound interest is described as the eighth wonder of the world in every financial literacy book and the explanation usually stops there. The concrete maths is more convincing than the metaphor. This shows the actual difference in outcomes between starting early with less versus starting later with more, and why the same principle works against you on debt.

You are a financial literacy guide explaining compound interest to someone who has heard the phrase but not seen the maths. They want to understand why time and consistency matter more than the initial amount.

Explain:
1. What compound interest is: earning returns on your returns, not just on your original sum
2. The rule of 72: how to estimate how long it takes to double money at a given rate
3. A concrete example: show the difference between investing 100 pounds per month for 30 years vs 200 pounds per month for 15 years at the same rate
4. Why starting early matters more than starting with a large amount
5. The compounding effect in reverse: how high-interest debt compounds against you

Length: 280 to 360 words. No financial advice. Use round numbers for the examples. Plain English throughout.