🎙 The 4% rule is a common rule of thumb used by financial experts for decades to determine how much money you need for retirement. But it’s not necessarily the best advice for a number of reasons, especially when you’re aiming to FIRE and retire many years earlier than traditional retirement. So why doesn’t the 4% rule work? And how do you then determine how much money you need to be able to retire? 🤔
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Hey, friends! And welcome back to Girl on FIRE, the financial independence podcast for independent women.
My name is Priya, I’m a Chartered Accountant, an analyst and the creator of Paper Money Co.
I’m also a fierce financial feminist and the host of this podcast. I believe that a woman who is in control of her money, is in control of her life.
This week we’re talking about the 4% rule for investing and retirement. It’s also sometimes known as the 4% withdrawal rate or the 25 times rule.
We’re going to talk about what it is, where it comes from and what it means for your wealth and retirement.
We’re also going to talk about whether or not it actually works. Because it’s a common rule of thumb, and you know how I feel about those.
But before we get started, I want to remind you to head to my website — papermoneyco.com/startinvesting and download your free copy of my Investing Starter guide
It’s totally free, you just need to enter in your email address and I’ll send it straight to your inbox. And then I want you to start working through it.
It gives you a plan to follow, step-by-step instructions to get ready to start investing and building real wealth.
If you’re really serious about learning to master your money, then it’s the perfect guide for you, and I’d hate for you to miss out on it.
As always, Girl on FIRE is about learning, so whip out your favourite notebook or journal and get ready to take some notes.
If you’re not into writing things out by hand, you can always find the transcript on my website — papermoneyco.com/gof23.
Okay, let’s dive in!
What is the 4% rule?
So, what is the 4% rule? The 4% rule is a commonly used rule of thumb to determine how much of your investment portfolio you can withdraw as income without running out of money.
And by doing that, it’s also used to determine how much money you need to be able to retire, whether that’s traditional retirement or early retirement.
Now, it’s certainly more complicated than that, which we’ll get into in this episode, but that’s the gist of it.
It came from a 1994 study by an investment manager named William Bengen and really started gaining traction after a 1998 study called the Trinity Study.
In his study, Bengen explored sustainable withdrawal rates for retirement portfolios for 30-year rolling retirement periods in the US from 1926 to 1963.
And based on his research, he determined that 4% is the highest initial withdraw rate that would allow the retirement portfolio to last 30 years regardless of market conditions.
So, the 4% rule says that you can safely withdraw 4% of your retirement portfolio (adjusted for inflation) as income for 30 years before you run out of money.
For example, if your retirement portfolio is worth $800,000, then using the 4% rule, in your first year of retirement, you can withdraw $32,000.
And then each year, you’ll adjust your 4% for inflation and withdraw that amount.
The 25 times rule
Now, the 25 times rule is just the 4% rule expressed in a different way. It tells you how much money you need in your portfolio to be able to withdraw 4% (adjusted for inflation, of course).
For example, if your annual expenses in retirement are expected to be $40,000, then your retirement portfolio would need to be $40,000 multiplied by 25, which is $1M.
As for where the 25 comes from, that’s just mathematical — 1 divided by 4% is 25, 1 divided by 3% is 33 and 1 divided by 5% is 20. It’s just changing the mathematical expression.
So, that’s what the rule is and where it comes from. It comes from the same place as the 4% rule.
The Trinity Study, the 4% rule and the 25 times rule are often cited in the FIRE community, so you may have heard of them before.
That’s what people call their FIRE number — essentially, how much their portfolio needs to be worth for them to tell their bosses to F off and retire early.
So, your FIRE number is basically the same thing as “how much do I need to retire?”. It’s just that with FIRE ,you’re retiring earlier than the government imposed retirement age.
Now, the Trinity Study was also updated by it’s original authors in 2011 and they basically came to the same conclusion.
But what I want to do in this episode is to put it under a bit of scrutiny. Does it really work? Does it work now in 2021 and all over the world when planning for early retirement?
Drawbacks of the Trinity Study and the 4% rule
Now, to determine whether or not the 4% rule is good enough for us, we need to look at some of the assumptions that were used in the study.
Because financial models can’t take every situation into account, so they need to draw some assumptions.
And I know this from years of experience in building models myself. As an analyst, I can create the most comprehensive and robust model I possibly can, but I can’t account for every possible situation under the sun.
You have to make some assumptions about the data you’re using or the scenarios you’re testing.
And those assumptions might not make sense for your circumstances, which means that the 4% rule might not work for you.
So, whenever you read or hear anything about studies and research it’s always super important to understand what assumptions are being used in the study.
And you’ll see that a lot of the assumptions made in the Trinity Study are actually limitations and drawbacks of the 4% rule.
Trinity Study 4% rule: 30 year retirement period
So, first up is the time horizon. A lot of the time on the internet if you hear people in the FIRE community talking about the 4% rule, they define it as how much you can withdraw without running out of money.
And that’s simply not true. This is often overlooked, but the Trinity Study didn’t calculate withdrawal rates on the assumption that the investor never runs out of money until they die.
The 4% rule actually only assumes a 30 year time horizon. It means that you can safely withdraw 4% of your portfolio to last you the next 30 years, which isn’t necessarily the end of your life, especially if you’re retiring early.
Now, in the 90s when the study was done, FIRE wasn’t really a thing. People were still expecting traditional retirement in their 60s.
So, looking at a 30-year time horizon kind of made sense. Because in 1998, when the Trinity Study was done, the overall life expectancy at birth in the US was just under 77 years.
And I’m quoting US figures here because the study was done based on US data which we’ll talk about a bit later in this episode.
So, if you retired at 60 or 65, your 30-year time horizon would get you to 90 or 95, so your retirement money would outlive you by a good 10 - 15 years.
But that doesn’t work so well nowadays. Because, for one, life expectancy has changed. It’s increasing. The overall life expectancy at birth in the US now is about 80 years.
But more importantly, there are a lot of people who are trying to retire earlier than 60 or 65. That’s what the whole FIRE movement is.
If you retire at 50, then with a life expectancy of 80, you’ll only just fall inside the 30-year time horizon of the Trinity Study and the 4% rule.
But what if you retire at 50 and live until 85 or 90. In those last 5 or 10 years of your life, you may not have enough money because your retirement portfolio would already have been depleted.
Or what if you retired at 45, like I’m hoping to, and you lived until 85. That’s 40 years. The 4% rule only covers a 30-year time horizon. So, what about those last 10 years?
I’m not saying that you’ll for sure be in poverty. I’m saying that the study that the 4% rule is based on didn’t consider that you’ll be in retirement for that long.
And it’s important to remember that if you’re using the 4% rule for your retirement planning, especially if you want to retire early. Because there is no loan for retirement.
And the government won’t help you. Do you hear me? The government will not help you.
The aged pension is barely enough to survive on, let alone live comfortably on. Your retirement is up to you.
Trinity Study 4% rule: Does it include women?
The next limitation that I want to draw attention to is that fact that based on the research I did for this episode, it doesn’t appear that the Trinity Study took the special circumstances of women into account.
And by that, I mean things like life expectancy. According to the World Health Organisation, women live on average 6 - 8 years longer than men do.
And we talked about this way back in episode 2. Because women live longer, we have a higher risk of running out of our retirement money. It’s called longevity risk.
And that’s so sad to me. This happens to so many women and it’s heartbreaking.
I don’t want it to happen to me. Throughout my whole life, I’ve worked my booty off to make sure I can always support myself.
I worked my booty off to get a good education that led to a stable job with decent income.
Even if that job was toxic. Even if I was facing workplace bullying every day for years. Even though I was miserable and I hated my life.
And the possibility of enduring all of that for 40 years to end up in poverty when I’m an old lady terrifies me.
How am I supposed to go get a job when I’m 82 years old? Will I even be healthy enough to work? How will I cover medical expenses?
And I’m still hoping to retire at 45. So, based on the 4% rule, my money will last for 30 years of retirement.
Which means I’ll be 75. And I hope I’m lucky enough to live a little longer than that. But I don’t want to do it in poverty.
Trinity Study 4% rule: Historical performance in the US
Another drawback is that the research underlying the 4% rule is done using historical US data.
Now, there are two important things to note here. One, historical performance doesn’t guarantee or predict future performance.
The research assumed a return of 10.3% on stocks, 5.2% on bonds and inflation rate of 3%. And that was based on the historical data that was available at the time.
But historical data doesn’t predict the future. Anything can happen, and one day those rates may no longer be relevant.
And the other thing is that those historical figures are based on the US market. So, the study isn’t as applicable in other countries like Australia.
In fact, Wade Pfau who is an academic with a specialty in retirement income has a website called Retirement Researcher.
And he commented on the 2011 update of the Trinity Study and said that the “4% rule has not held up nearly as well in most other developed market countries as it has in the US”.
So, for my listeners in Australia, you need to take that into consideration when planning your retirement.
But then, what withdrawal rate is safe for us to use? Aussie HIFIRE is a blogger in the Australian FIRE community and he recreated the Trinity Study using Australian data all the way up to 2016.
And based on his model, the safest withdrawal rate was 3% not 4%. So, you’d have to take your annual expenses in retirement and multiply by 33 not 25.
For example, if your annual expenses are $50,000, you’d need a portfolio value of $1.65M.
Under the 4% rule, you’d need only $1.25M. That’s a difference of $400,000. I’ll leave his article linked in the show notes if you want to check it out.
So, again you can see that the 4% rule isn’t gospel.
Trinity Study 4% rule: Based on stocks and bonds, not real estate
Another thing to note is that the Trinity Study and the 4% rule is based on stocks and bonds. Remember, it assume a 10.3% return on stocks and 5.2% return on bonds.
It doesn’t include a real estate portfolio. And that kind of makes sense, right? Because you can’t withdraw 4% from a portfolio of real estate. Real estate isn’t a liquid asset.
But a lot of the time out there on the internet, you’ll see people calculating their FIRE number and their progress towards that number.
But they’ll include their real estate holdings in that as well. And that could be problematic.
Especially in places like Australia, we’re in a massive real estate bubble. Old houses that honestly should be knocked down are selling for over $1M.
And if you purchase a house like that, yes you take on a massive mortgage, but it also adds to your assets overnight.
And as the property values keep increasing until the bubble bursts, your net worth is going to increase dramatically. We talked about net worth in episode 11, so if you’re a bit confused, go back and listen to that one.
That can make it look like you’re getting closer and closer to your FIRE number, but you can’t draw down on real estate like you can with stocks and bonds.
You’re going to have to sell it to get your hands on that cash, and that’s a piece of work all on it’s own. And once your real estate is sold, you’re not making any more returns from it. So, it’s not the same thing.
For example, let’s say that your portfolio gets to $1M and you’re ready to retire early. But $700,000 of that, 70% comes from the value of the real estate you hold.
You don’t get access to that as income to live on. You might be making money on it by renting it out, but at least in Australia, rental yields are really low because property values are too high.
We’re in a big bubble. There’s only so much you can make off your tenants.
But you can’t just withdraw 4% from your real estate holdings. You’d need to sell it to get your hands on that cash.
But what if you don’t sell it? What if you’re making rental income but it’s all going towards property management expenses, so nothing in your pocket?
That mean you only have $300,000 of your total portfolio that you can actually withdraw for income in retirement.
And under the 4% rule, that’s $12,000 a year. That’s nothing.
FIRE & investment calculator spreadsheet
Before we move on, I want to ask my Girls on FIRE for a favour. If you’ve listened this far into the episode then you’re probably enjoying it, right?
So, here’s what I’d like you to do next. Pause this episode for a few seconds and head on over to papermoneyco.com/podcastreview.
I want you to leave a rating and a review for Girl on FIRE because that helps me provide better content and it helps other women out in the internet wilderness come and find us.
It’s also a great way to support this show for free and I’d love to send you a little something to say thank you.
If you do that, I’ll send you a copy of my FIRE and investment calculator. Which, if I do say so myself, is pretty damn amazing.
It’s how I plan for my early retirement and my wealth. It shows me how my wealth is going to grow, when I can retire and how long my money will last.
And it also has a separate tab that takes Australia’s superannuation into account as well.
And you can use it to analyse companies and different investment options when you’re picking stocks too.
I’ve never actually seen anything like it before, so it’s pretty special. And I’m currently not offering that spreadsheet anywhere else except on Patreon.
Not in my shop, not to my email list — it’s a ghost. So, this is kind of a money-can’t-buy type deal.
The only way to get your hot little hands on that spreadsheet is by leaving a rating and a review, taking a screenshot and tagging me in it.
That URL again is papermoneyco.com/podcastreview. I’ve made it nice and easy for you.
So, go hit pause and do that right now. It’s okay, I’ll wait.
Okay, that concludes my little ad-break, so let’s get back to it.
Trinity Study 4% rule: Portfolio asset allocation
The next drawback I want to address about the 4% rule is that the original Trinity Study in 1998 assumed that the investor maintains a balanced portfolio of 50% stocks and 50% intermediate-term treasury bonds.
And then when they updated it in 2011, they said that a withdrawal rate of 4-5% was suitable for portfolios of 50% or more in large-company stock.
Now, we talked about stocks and bonds in episodes 14 to 18, if you want to go and check that out.
But we know that stocks are inherently more risky than bonds. So, the study has actually been criticised by some experts for being too risky.
Because the truth is that because bonds are generally considered to be safer, their yields aren’t very high. The lower the risk, the lower the returns.
Now, when your time horizon is longer and you have the ability to take on risk, more of your portfolio is generally allocated in stocks than in bonds.
Retirement and your asset allocation
So, for example, you might be super aggressive and have 100% in stocks,
Or if you’re trying to grow your portfolio but you want to be a little bit conservative, you might allocate 30% to bonds and 70% to stocks.
And then as you get closer to retirement, your time horizon shrinks. Which means that your risk tolerance becomes lower.
You can’t afford to lose everything now, because then you’ll have to go and get a J-O-B and no one wants that!
So, then you rebalance your portfolio to be 50% in stocks and 50% bonds — an even 50/50 split.
And as you get even closer to retirement, you adjust it to 70% bonds and 30% stocks.
Do you see how in this example, the portfolio is being allocated away from riskier investments and towards safer investments as the time horizon gets shorter?
And now retirement is coming up really soon, so you rebalance your portfolio again and go 70% bonds, 20% stocks and 10% cash.
This is just an example using arbitrary numbers. Your asset allocation needs to depend on your investing strategy.
But I’m trying to show you how your asset allocation changes as you’re getting closer to retirement.
So, if you’re in retirement and starting to draw down on your portfolio for income, a 50/50 allocation between stocks and bonds as suggested by the 4% rule might be waaaay too risky.
The stock market could take a nose dive tomorrow and you could lose half your portfolio.
Of course, it’ll rebound, it always does. But what if it takes 5 years? And what if during those 5 years, you don’t have enough income because your portfolio is half the woman it used to be?
And like I said in episode 18 when we talked about bonds, you could go super conservative and put the majority of your money in bonds right from the start when you still have decades to go.
But you’re really limiting your returns and the growth of your wealth. Because bond returns just aren’t as high as stock returns. And that’s because they’re less risky.
So, this is my educated guess: the study says to have 50% or more your portfolio in stocks because returns from bonds aren’t high enough to sustain your portfolio.
Because you aren’t withdrawing it all at once. You’re only taking out 4% and the remainder of your portfolio keeps growing until next year when you withdraw again.
But if you’re heavily invested in bonds, the remainder of your portfolio will yield lower returns and grow slowly. So, you need to be invested in stocks so that your portfolio keeps up with your withdrawal.
That’s just my guess. Because recommending a 50/50 allocation between stocks and bonds in retirement is super risky.
So, that’s just something to think about.
Some experts have also done another study and in 2013 published a paper saying that a 4% withdrawal rate isn’t safe when interest rates are so low like they are nowadays compared to back in the 90s.
Because back then when interest rates were higher, bond and dividend yields were also higher. Which means that even though you were taking money out of your portfolio, the rest of it was still growing.
But nowadays, it might not be growing fast enough to keep up with your withdrawals. You’re eating your cake faster than new cake can be made.
Total side note here, I just found out that you can Uber Eats from the Cheesecake Shop. That means I can have cake delivered to my home and my life has just changed.
Trinity Study 4% rule: Consistent annual withdrawals
Okay, so, next up, the Trinity Study assumes that you’re withdrawing the same amount of money every year.
Now, it is adjusted for inflation, which the study assumes at 3%. So, you’re withdrawing 4% in the first year and then in the subsequent years, you’re withdrawing 4% adjusted for 3% inflation.
It’s assuming that your expenses never change, apart from inflation. But that’s not really how life works.
You might get sick and have a few extra medical bills, especially as you get older.
Or you might take a huge international trip every couple of years, and that increases your costs in those years too.
Think about all the things you would do right now if you didn’t have to go to work. When you’re retired, you actually get to do those things and the truth is that most of those things will require some form of expense.
Also, you might decide to withdraw less in a bear market to minimise your losses. And you might decide to withdraw more in a bull market and live a little more lavishly.
But the 4% rule doesn’t take that into account. It assumes that you’re withdrawing 4% adjusted for inflation every year for 30 years.
Trinity Study 4% rule: Retirement and taxes, fees and inflation
And the last drawback I want to talk about today is the fact that the Trinity Study doesn’t take taxes and fees on mutual funds into account.
So, you might be getting a 10.3% return on stocks and 5.2% return on bond with 3% inflation just like the study assumes.
But you still have to pay taxes. And you still have to pay mutual fund fees, or even just a management expense on an ETF.
And that reduces how much money actually ends up in your leather Kate Spade wallet when you withdraw from your portfolio.
Any mutual fund or management expense fees you have to pay will depend on what you’re invested in and they’ll eat into your returns.
And you’ll also be taxed on any dividends, interest and capital gains that you make. But the study doesn’t include those things.
So, if you were to withdraw 4%, you’d have to use that income to cover those taxes. Taxes don’t stop just because you’re retired. Governments aren’t that nice.
Now, as I said before, I know from my experience with building financial models that you can’t always account for every single scenario.
So, I’m not saying that they did the wrong thing by making these assumptions. You have to make assumptions.
What I’m saying is that if your life and your circumstances don’t reflect these assumptions 100%, then the 4% rule isn’t going to apply to you 100%.
And that means that you need to be cautious when using rules like this. Because you could be planning your retirement using a rule that’s based on a lifestyle and investing strategy that’s completely different to your own.
How Priya determines how much she needs for retirement
Okay, so now that I’ve spent all this time talking about why the 4% rule doesn’t always work, let’s talk about what I actually use to plan how much money I need for retirement.
And the answer isn’t as simple as multiplying my expenses by 25 or any other number, but for me, it’s more robust, which is why I like it.
It’s not based on a benchmark or a rule of thumb because we know how feisty I get about those.
So, this is what I do. First, I estimate my expenses in retirement. And I’m generous here. I’m hoping to spend a ton of time travelling and enjoying myself.
Which means I need money to cover those expenses. So, I’m planning for my expenses to increase in retirement.
It’s common to assume that your expenses go down in retirement and sometimes they do, but not always.
You might not be spending money on work lunches or commutes anymore, but you’ll likely be spending money on different things.
So, don’t fall into the trap of assuming your lifestyle will be cheaper in retirement. That’s not always the case.
Estimating expenses in retirement with the 4% rule
So, I’m currently planning for my annual expenses in retirement to be $70,000. Yes, my expenses could change from year to year.
But I’m an anxious person, and I want to be conservative here. So, that $70,000 should cover most situations that retired Priya finds herself in.
I think in a previous episode I mentioned that I was planning with $60-$65,000 but clearly since then, I’ve decided to live a little larger, so my target has changed a bit.
The next thing I do is I determine how long my retirement is going to last. So, that’s the number of years between when I retire and when I die.
Now, FIRE with Australia’s superannuation retirement system can get a little bit complicated. It’s definitely something I want to dedicate a whole episode to.
But for simplicity’s sake in this episode, let’s assume that I’ll retire at 45 as planned and my brokerage and retirement accounts are combined.
We’ll ignore the age restriction for accessing retirement accounts in this scenario, because that complicates things a bit. We’ll talk about that in a future episode.
So, I’ll retire at 45 and my retirement money needs to last until the end of my life 40 years later at 85, if I’m lucky.
And I’m taking my life expectancy as 85 because that’s what the statistics say plus a little extra in case I happen to live a little longer.
Life expectancy at the time I was born was about 80 years for females in Australia. And I’m padding that by 5 years, just in case.
That means I’ll need to cover $70,000 of annual expenses, adjusted for inflation, for 40 years.
You can already see that the 4% rule isn’t going to work for me, because it’s based on a 30-year retirement, not 40 years.
Calculating my FIRE number
Now, what my FIRE calculator spreadsheet does is it takes the sum of those expenses over 40 years, adjusted for inflation, and tells me how much money I need in my retirement account at 45 when I retire to be able to cover 40 years of expenses.
It tells me how much I need at the starting line to last me until I get to the finish line. This is called calculating the present value of my future expenses.
How much money will I need in my nest egg on the day I retire to last me until the end of my life 40 years later.
Now, I assume an 8% overall return for my entire portfolio adjusted for 2% inflation, and it’s after things like fees and taxes, so I’m trying to be conservative here.
That tells me I’m going to need about $1.6M to fund 40 years of retirement.
To me, that’s a much more robust and personalised way of figuring out how much money I need to retire.
It’s based on my investing strategy, my lifespan and my retirement plans.
Because, remember the assumptions of the 4% rule: 10.3% return on stocks, 5.2% return on bonds with a portfolio that’s 50/50 allocated in stocks and bonds, and 3% inflation for 30 years.
So, using the 4% rule, with annual expenses of $70,000, I’d need $1.75M. Which is an extra $150,000.
But it’s also based on the assumption that I’ll spend only 30 years in retirement, not 40.
And it’s also assuming that my asset allocation is going to be 50% in stocks and 50% in bonds. And I don’t see myself doing that, because that’ll be too risky for me.
My portfolio is heavily invested in stocks now, because I have the time to risk being more aggressive. I’m only 29, I have at least 15 years until early retirement and even longer until traditional retirement.
Right now, my priority is growth, but as I get closer to retiring, my asset allocation will change.
So, that’s why in my FIRE and investment calculator, I’ve purposely made the model dynamic so that you can change your withdrawal rate.
And in the tab with the Australian FIRE calculator, where I take our retirement system into account, I’ve set it up so that I can switch between using the withdrawal rate or using the present value of my expenses.
Another thing is that using the 4% withdrawal rate, my figures currently have me on track to retire at 45. Which is great, that’s my goal.
But when using the present value of my expenses to calculate my FIRE number, I should reach my goal by 44.
And if someone told you that you could retire a year early, would you really say no?
Next weeks’ episode
And that’s all I have for you Girls on FIRE today!
My challenge for you this week is to head to papermoneyco.com/startinvesting and download your free copy of my Investing Starter guide.
It gives you a step by step plan to follow to get your finances ready to start investing, including working with a budget, building an emergency fund and paying off debt.
You just need to enter in your email address and I’ll send it over to you.
The sooner you can get your foundation set and get those good money management practices in place, the sooner you can start investing and building your wealth.
On next weeks’ episode we’re going to be talking about dollar cost averaging which is an investing strategy often used to reduce volatility in the stock market.
It’s going to be a super interesting episode so you’re definitely not going to want to miss it.