Finance

Personal Compound Annual Growth Rate Calculator (15 Years)

Calculate compound annual growth over a period. This personal version uses a 15-year planning term as its starting point.

What this means: the CAGR is the single steady yearly rate that would turn the starting value into the ending value over 15 years, so it summarises the whole period as one average yearly pace rather than showing each separate year.

Formula

CAGR equals ending value divided by starting value, to the power of one over years, minus one.

How it works

CAGR smooths growth into a single yearly rate, even if actual yearly growth varied.

Worked example

Starting value $10,000, ending value $20,000, term 15 years. First, the growth ratio is $20,000 divided by $10,000, which is 2.00. Using the CAGR formula, the rate is 2.00 to the power of one over 15, minus one, which is 4.73% a year. Check it back: $10,000 times 1.0473 to the power of 15 is about $20,000. Total growth is $10,000, or 100% over 15 years, yet the yearly rate is only 4.73%, because 15 years of compounding turns a modest yearly rate into a doubling.

Who this term suits for a person: A 15-year term suits a person at a mid-career point, for example building a retirement seed, planning around a mortgage horizon, or saving for a child's university costs. A 4.73% yearly rate looks modest, which is exactly why it needs an inflation check: if prices rose faster than 4.73% a year, the $20,000 at the end buys less than $10,000 bought at the start.

FAQs

What does CAGR mean?
CAGR is the steady yearly growth rate that would take a starting value to an ending value.

Is this personal calculator exact?
No, it is an estimate for planning only, based on the numbers you enter.

Are these figures financial advice?
No, they are estimates for planning only, not financial advice. Check with a qualified adviser for decisions involving large sums.

Why does the rate fall to 4.73% when the money still doubles?
Because time does more of the work. The same doubling spread over 15 years instead of 10 needs a lower yearly rate, since compounding runs for 5 extra years. A lower CAGR over a longer term is not a worse result, it is the same result measured over more time.

How does inflation change a 15-year CAGR of 4.73%?
This calculator gives a nominal rate, before inflation. If inflation averaged, for example, 3% a year over those 15 years, the real growth would be roughly 4.73% minus 3%, or about 1.7% a year in buying power, not 4.73%. The page does not include inflation, so a real-terms check is needed separately.

Can a 15-year CAGR help with a house deposit plan?
Yes, as a reality check. If a deposit fund doubled in 15 years at 4.73% a year, compare that with house price growth over the same 15 years. If house prices grew faster, the deposit may still fall short, even though the fund doubled in cash terms.

Estimates only, not financial advice. Figures are approximate and do not include all fees, taxes, or changing rates unless stated.