Just came across an incredibly interesting thread on Bogleheads on Variable Percentage Withdrawal (VPW):
http://www.bogleheads.org/forum/viewtopic.php?f=10&t=120430&p=1761580#p1761563I'll try my best to summarize the idea. Let's assume you have a yearly spending rate of $40,000, here are some possible withdraw strategies:
1.
The standard 4% rule, also referred to as "Constant-Dollar". So you amass a $1,000,000 portfolio, and withdraw the $40,000 plus inflation each year. You are now Financially Independent, and can retire. The risk of this advice, is that you're subject to a bad sequence of returns, in which case your portfolio can drop to 0. If the bad sequence of returns doesn't show up, it is likely you will leave a large amount of money unspent. And by the time you realize you have too big a pile of money, you might be too old to spend it.
2.
Constant-Percentage, where you withdraw 4% of your portfolio each year, even if that number ends up being less than your $40,000 yearly spending. If you retire on a $1,000,000 portfolio, you'd have to be prepared to take up a side job if the portfolio doesn't provide the required $40,000 plus inflation. This one does not have as much sequence of return risk. The problem is that I am, again, quite likely to underspend and leave a lot of money unspent. If I choose a higher percentage, it might be too high, leading to fast depletion, or too low, leading to lots of unspent money.
3.
Spend only the dividends. At today's rates you'd need to save up significantly more money, or invest in significantly riskier assets, in order to live on just dividends. To quote Senior Mustachian Sol, when people recommend this, "It's almost like you're a force of evil in the world, trying your hardest to keep people from finding happiness by suffering extra decades in soul-crushing jobs. Stop it."
4.
The Variable Percentage Withdraw (VPW). While the methods above try to ensure your portfolio lasts forever, VPW aims to deplete the portfolio during a specified time period (by default, when you turn 100 years old). The OP of the Bogleheads thread (Longinvest) says this about other withdraw methods, "by withdrawing less in the earlier part of retirement, you are deferring your consumption from when you have the health and ability to enjoy it with your loved ones, only to save it for later days when you will be very old and have little ability to make good use of it."
VPW will always withdraw a higher (absolute) amount money than Constant-Percentage, with the important difference that VPW will deplete your portfolio while Constant-percentage won't. VPW adapts to the effective returns (gains or losses) of your portfolio. It will not fail if a bad sequence of returns happens at the start of your withdrawal phase. It will also increase your withdrawals if your portfolio gives you returns above what was expected. Similar to Constant-Percentage, I need to be prepared to get a side-job if the portfolio doesn't provide the required $40,000 plus inflation.
I think the VPW fits perfectly for Mustacians who want to retire early, and have hobbies/activities which will likely be bringing in a bit of money anyway. Especially since Mustacians are much less susceptible to inflation than the average person, so nominal returns go much further with us. The Longinvest discusses this
here.
To highlight this, I downloaded
the calculator, and put in the numbers for a 35 year old who has $40,000 yearly spending, retiring from the 9-5 with $600,000 saved up:

Here's what the withdrawals look like using data starting in 1945:


You will definitely be relying on the side job for the first few years, but after a few years it probably won't be necessary. Over the 65 years in the example above, you will have withdrawn a total of $21.7 million, all on the $600,000 initial portfolio size. This also assumes you won't bring in any more money than required from the side jobs, which seems unlikely.
Longinvest gives a fantastic argument for VPW
here, and the FAQ is available
here for more details, but really that's the main idea.
I'm seriously considering using VPW with my portfolio, before the standard 4% rule would indicate I'm ready. Is this riskier than I'm making it out to be? What do you think?