Comparing 4% vs. 8% Investment Returns

Thought experiment: Person A invests \$5,000 each year for 20 years and earns 8% annual returns. Person B invests \$7,979 each year for 20 years and earns 4% annual returns. Which person will have more after 20 years?

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It turns out that they will both have \$247k.

Although person A experienced two decades of solid 8% annual returns compared to the mediocre 4% annual returns of person B, the higher savings amount by person B allowed her to make up the difference in investment returns.

The table below further illustrates this point. It shows how different annual investment amounts can lead to the same ending amount after 20 years, despite differences in 4% and 8% annual returns:

The chart below shows another way to visualize these numbers. The size of the circle represents the ending value after 20 years. The-x axis represents the annual rate of return on investment. They y-axis represents the yearly investment.