Applying the rule of 72 to my historical gains.

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Past performance being no guide to future returns and all, I just thought I'd try this little exercise for fun. I have an old pension pot which I'd not added to since 2004, so I thought I'd plot its progress on a simple line graph. Fees are < 1%.
I was pleasantly surprised to actually see the much mentioned compound effect showing the line pretty closely matching the exponential trend line over 21 years. The was a bit of positive deviation during covid (heavy in tech), then a downturn at the end due to last years higher interest rates but all in all I see a rough doubling of the pot every 7 years.
Not that I take this to mean anything for future returns, but it does give a nice fuzzy feeling that the maths actually does work when applied to your own figures.
I was pleasantly surprised to actually see the much mentioned compound effect showing the line pretty closely matching the exponential trend line over 21 years. The was a bit of positive deviation during covid (heavy in tech), then a downturn at the end due to last years higher interest rates but all in all I see a rough doubling of the pot every 7 years.
Not that I take this to mean anything for future returns, but it does give a nice fuzzy feeling that the maths actually does work when applied to your own figures.
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I can’t wait to start putting money in my sons SIPP for him and start watching.
Since the OP makes no mention of the Rule of 72, I will for the benefit of those who don’t know.
The Rule of 72 relates to compound interest and the time it takes for an investment to double.
If an investment earns 8% interest and is left untouched, it will double in about 9 years. 8 x 9 = 72
“If I earn 6%,how long will it take to double my money?” 72 / 6 = 12. So it will take 12 years.
“If I want to double my money in 4 years, what growth rate do I need to achieve?” 72 / 4 = 18. So you need to achieve 18% compound growth.
Simples
In the OP's case, his pot is doubling every 7 years, so he is averaging just over 10% growth.Why bother if you have the rule of 72? Because now your phone will do tripling growth, or 4.5 times growth, or 17 years of growth.