Who likes making money? Payback, RoI, IRR explained…

What’s a payback period? How does it compare to Return on Investment and Internal Rate of Return?

A good question. A payback period is the time it takes for the benefit of a project (cost savings or increased revenue) to pay back the initial capital of the project. For example, you have a project that costs $2,000 and takes a year to complete. After it is completed it saves you $1,000 yearly (no end date in this example). That means the project will take 2 years to be paid back after the project’s completion ($2000/($1000/year) = 2).

So how does this compare to Return on Investment (RoI)? Simple ROI = (Gains or savings – investment costs) / Investment Costs. It does not take time into account. For instance, with the above example, after 3 years the RoI is ($3000-$2000)/$2000 = 50% but after 10 years the ROI is ($10,000-$2,000)/$2000 = 400% – so the RoI keeps escalating toward infinity over time… not very useful. Internal Rate of Return (IRR) however, is!

IRR is a compounding rate of return. I won’t go into the calculation but the above example has a ~50% IRR. Since it’s compounding we can use the “rule of 72” to figure out what this really means. The rule of 72 tells us how many years it takes to double the cumulative benefit. So 72/50= 1.44 years. So at 1.44 years the gain/savings is $1,440. At 2.88 years it is $2,880. At year 5.76 it is $5,760. And so on…


At left is the compounding “hockey stick” graph. This is the hockey stick graph for my “rewirement” strategy (9% compounded yearly) – coincidently this is the same strategy that I coach about. It’s the only buy and hold strategy that works in an up or down market, has over 150 years of market data behind it, is the laziest DIY strategy and that most anyone can do (assuming you understand addition, subtraction, multiplication and division).

A slow start initially and then ZOOM! upward. Compounding in action!

If you are interested in this strategy, I read about it in a book that is freely downloadable on the internet or you can get the book from a library or a used bookstore:

“The Single Best Investment: Creating Wealth with Dividend Growth by Lowell Miller”

I liked reading it but many people tell me it’s boring… I guess I get excited enough about making money to read it through. What I coach in is the “how to” part; complementary to the book (or for people who don’t want to read it and want the summary). People are fully coached in approximately 2-4 hours depending on the person (2 hour basic course plus additional time as needed). However, I love to support “do it yourselfers”, and if you are one, you can probably figure out the “how to” part using Mr. Miller’s book with some invested time. However, if you want a jump start, please let me know!

I actually asked Mr. Miller if it was ok if I coached people using his book as the basis. He said “sure!”. You have to wonder… this strategy 100% works; always! Mr. Miller has published two versions of his book over the last decade+ before finally allowing people to read it for free on the internet. Clearly, people aren’t using it en masse. Every single person I have coached says “Why doesn’t everyone do this? It’s so easy!” and “I wish I had done this X years earlier.”  No one has ever told me “this is a waste of time”. Mr. Miller is a fund manager – which the book basically discourages using. And even after Mr. Miller tells his clients not to use him and how to do it themselves, they still want Mr. Miller to manage their money.  Such a strange world we live in!

Note: I owe recognizing the strength of this strategy as I read that book to my knowledge of IRR and payback periods. Good things to know!

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