UPDATE: For an interesting follow-up to this post, see **The Rule of 72, 114, and 144**

Have you ever wondered how long it would take to double your money? Triple? Quadriple? The answer depends on the rate of return. Naturally, the higher the rate of return, the less time it takes to double, triple, or quadruple your investment. It’s not hard to figure out if you have Excel, or you can just use the three graphics I created:

NOTE: Keep in mind that these graphics assume linear (straight line) growth, which *never* happens in the real world.

**To Double Your Money…**

**To Triple Your Money…**

**To Quadruple Your Money…**

So, if you have $100,000 in your retirement account and you get an annual rate of return of 8%, it will take 18 years for that original $100,000 to grow to $400,000 (not counting any additional contributions).

I just thought you’d like to know.

Related:

“Keep in mind that these graphics assume linear (straight line) growth, which never happens in the real world.”

That’s not actually true. They assume constant growth rates which generates decidedly non-linear growth in the balance of your account.

This is a chart form of the rule of 72. The rule let’s you know how long to double your money. Divide 72 by the rate of return and you get how long it takes to double the funds. Example $100 earning 8% takes 9 years to double. (and 18 years to quadruple ). I like it because I can do it in my head or with a handy calculator- no chart needed.

…well, OK… but what will those future dollars actually be worth (purchasing power) ??

That’s what one really wants to know for planning.

Need a method to factor “inflation” into such ‘growth’ equations.

Real U.S. inflation is currently running 5-10% per year, despite lesser pronouncements from the Federal bureaucracy.

[Bonus Question: what causes inflation ?]

HagenT,

You are correct. I ignored inflation in this calculation.

“Real” inflation? Is that inflation adjusted for inflation? 5-10% per year? If that’s the case, you might as well be keeping your money under the mattress.

In order to take inflation into account, just use the ‘real’ return (return – inflation) when using these tables.

So, at 9% interest and 3% inflation, your buying poer doubles in 11.9 years. Using this method, 6% is about the highest you could expect.

> graphics assume linear (straight line) growth, which never happens in the real world.

Well, it wasn’t THAT long ago that you could get a bond at 6%.

This might interest your readers. This Dividend Calendar displays companies by their Ex-Dividend Date:

http://sp500.us/dividends.php

You may also sub-sort the list by Stock Symbol, Company Name, Market Cap, Yield, Rate, or Payment Date.

well it is really great to see it but just doubling money is not enough for me..i want it to Quadruple every 6 months …greed never ends…