The Motley Fool Discussion Boards

Previous Page

Investing/Strategies / Retirement Investing


Subject:  Re: Strategy comparison S&P500 vs. IUL [rev 1] Date:  4/7/2013  11:43 AM
Author:  Rayvt Number:  71768 of 88520

see how an IUL performs - both during accumulation, and distribution assuming the tax free loan status and continual crediting of the loan amount
Um .... forgot about this. Plain vanilla simple method is final value $29,800.

Need to figure accumulation of running balance minus outstanding loan minus 6% interest.
Let's assume we don't reduce the value by the draws, but keep track of the draw amount and the interest owed in a side account.
We'll let it grow, then at the end offset by subtracting the balance of this side account.

So play a game with the spreadsheet. Accumulation phase as before, to 1/1/2003, but then set withdrawal of $0 (this stops the deposits). See what final value is reported, and then subtract out the total amount of the side account.

SWAG on the loan interest. Avg balance of $100,850 (half of the total draw) at 6% per year = $6051/yr. Over 10 years that's $60,510.

Final SWAG'ed value: $286,500 - $201,700 - $60,510 = $24,300.
(Final value - total withdrawal - accumulated interest).

Oh, duh!! No need to SWAG -- excel is good at this kind of thing.
Ending balance of loan side account at 6% interest, computed monthly is $272,000. ($270,600 if computed annually.)

Final net value: $286,500 - $272,000 = $14,500.

Same ballpark as the plain Jane method, so all the fancy footwork with loans, etc. is just fancy-dancing with minimal real-world effect.

Also, we're not using a "single investment" of $1,000 but an agreed ongoing investment of X.
CC, what he did was a quick & dirty back-of-envelope smell test. Engineers & physicists do this all the time.
All you are trying to do is to see what ballpark the numbers are in. "Smell test" is like sniffing that lunchmeat in the refigerator --- you're not trying to get an exact freshness level -- you are just trying to see if it smells bad.

The value of this technique is that it is simple -- so simple that any methodology errors will be clearly obvious -- but that it will still give you a decent approximation to the results that have all the complexity. If the back-of-envelope number is way off from what you need it to be -- it smells and you know your idea is garbage, yo don't need to waste any more time & effort to be more exact.

Like he said, you can do this in 5 minutes. It's so simple that it would take as much time find it again after you've saved it as it would to just re-do it from scratch.
Copyright 1996-2018 trademark and the "Fool" logo is a trademark of The Motley Fool, Inc. Contact Us