In our post about Safe Withdrawal Rate (SWR), we showed relatively high success rates* for a 5% SWR with a mixed portfolio of stocks/bonds. But that was using simulated returns.
This chart shows the success rates using historical data going back to 1920. This portfolio is using 50% S&P500, and 50% bonds.
But what does 90% success for a 5% SWR mean? What does failure look like?
* This is not an endorsement for a 5% SWR. The intent is to show what happens when your SWR is too high.
Some Simulation Details
The modeled portfolio consists of 50% S&P500, and 50% bonds. (The actual simulation uses the 10YR U.S. Treasury rates + 1.0% as a proxy for investment grade corporate bonds. Reference: AAA vs 10YR Yield)
The chart shows nominal and real returns of this portfolio since 1913.
A 30 year retirement is modeled for years prior to 1995 after which the model stops at 2025.
Inflation matters
Note that in the 1960’s, nominal returns seem to follow the general upward trend, but the real return is flat. The nominal returns were similar to inflation; purchasing power stayed flat.
Failures Aren’t Random
This chart shows success/failures mapped onto the real return data; red means a retirement that started that year ran out of money.
Note that the “failure year” is the starting year of retirement, not the year the balance hit zero.
Key finding
The failures are clustered: 1937, 1962-69 (most years), 1973, 2000
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When you're planning for retirement,
there is one giant kind of scary
question, right? How do you make your
money last? Today we are going to dig
into a really popular rule of thumb that
promises an easy answer. But we're also
going to see what a hundred years of
data tells us about when that promise
can go really, really wrong. You know,
the biggest challenge in retirement is
turning that pile of savings you've
built up into a steady paycheck that you
can outlive. It's a super complex
problem. But for decades, people have
been looking for a simple fix. You know,
that one single number they can just
trust. Okay, let's make this real.
Imagine this is you. You've worked your
tail off. You've saved a million bucks.
So now what? Can you spend $30,000 a
year? 50,000? How about 70? If you pick
the wrong number, well, the consequences
are severe. This is the question that
keeps people up at night. And that
brings us to this key idea, the safe
withdrawal rate, or SWR for short. It's
supposed to be the magic percentage that
lets you sleep easy knowing your money
is going to last as long as you do. The
whole goal is to find the highest S SWR
that is still, you know, safe. So, what
does history actually tell us? Well, if
you look at the data going all the way
back to 1920, it's incredibly
reassuring, at least at first. A 3% or a
4% withdrawal rate has literally never
failed over a 30-year period. A perfect
100% success rate. I mean, that feels
like a guarantee, doesn't it? Now,
here's where it gets really interesting.
What happens when we push that number to
5%. Historically, even a 5% rate has
worked 90% of the time. Think about that
for a second. Nine times out of 10, you
would have been totally fine. Those
sounds like pretty good odds, right? So,
what's the catch? Well, the catch is
that 10% failure rate. Because when
we're talking about your entire life
savings, a 1 in 10 chance of running out
of money isn't just a statistic. It's a
potential disaster. We've got to
understand what exactly goes wrong in
that 10% of cases. So, let's ask the
most important question here. Is it just
random bad luck? You know, a stock
market crash here, a little inflation
there, or is there a specific
identifiable pattern to why these
retirement plans fail? And the answer,
when you look at the data, is
surprisingly clear. These failures, they
aren't random at all. They're caused by
one specific thing. Starting your
retirement at the absolute worst
possible time. This chart just
illustrates the point perfectly. It maps
out every single possible 30-year
retirement simulation since 1920. Each
green line is a success story. Each red
line, well, that's a failure. But notice
something. The red isn't just sprinkled
around randomly. It's all clumped
together in these few distinct dangerous
periods. This is our first major clue.
Okay, so let's put on our detective hats
and dig into this. If these failures are
all clustered together, they have to
share a common cause. So, what is this
hidden danger that connects these
specific moments in history? Okay, on
the left, you're seeing historical
investment returns. That light blue line
is the one to watch. It shows your
return after inflation. Now, look at the
chart on the right with our red failure
zones. See how right before each red
cluster kicks off, that light blue line
on the left just goes totally flat for
years? That's it. That's the connection.
And this brings us to the real villain
of our story. A long period of near zero
real returns. It really doesn't matter
if your portfolio goes up 7% on paper if
inflation is also 7%. Your purchasing
power, your ability to actually go out
and buy stuff has gone absolutely
nowhere. This is the danger hiding just
below the surface. And here they are,
the specific start years for retirements
that failed with that 5% withdrawal
rate. Every single one of these, 1937,
the late60s, 1973, and the year 2000,
was like a starting pistol for a long
grinding period where your investments
just could not outrun inflation. It was
the definition of bad timing. So, we
found the culprit. Now, let's look at
the anatomy of these failures. Because
it's one thing to see them on a
historical chart, but what does this
slow grind of low real returns actually
do to a retireese's bank account year
after year? This famous line from Ernest
Hemingway just perfectly captures the
terrifying nature of these retirement
failures. It isn't one single dramatic
market crash that does all the damage.
It's a slow, silent erosion that builds
for decades before the floor just
completely falls out from under you.
First, let's look at the 90% of cases
that actually worked out. In these
scenarios, that starting $1 million
portfolio either stays pretty level or
in a lot of cases, it actually grows
over the 30 years. This is what success
looks like and it's the most common
outcome which is good news. By now look
at the failures. These are the 10% that
ran out of money. For the first 15,
maybe even 20 years. The decline is
slow. It doesn't look like a five alarm
fire. But then the portfolio hits a
tipping point and just collapses
gradually and then all at once. And
here's the most crucial point. In every
single one of these historical failures,
the money didn't run out until deep into
retirement. We're talking 23, 26, even
29 years in. The real danger is that
you'd feel safe for two whole decades
thinking your plan was working with
absolutely no idea you are on a
collision course with disaster. Okay,
that was the bad news. I know. But
understanding the risk is the very first
step to managing it. Now that we've
unmasked the culprit, let's talk about a
simple, actionable strategy you can use
to protect your own retirement. Here is
your three-step survival guide. First,
just be more conservative. Start with a
rate that has a better track record,
something like 4%. Second, monitor what
actually matters, those real returns. If
you see your investments are struggling
to beat inflation for a few years in a
row, that is your big warning sign. And
third, be flexible. Having a plan to
temporarily cut back on spending could
be the one thing that saves your entire
retirement. And hey, if you need any
more convincing on being conservative,
just look what happens if you get a
little more aggressive and try a 6%
withdrawal rate. The success rate just
plummets from 90% all the way down to
67%. A third of all retirements would
have failed. And failure happens way
faster, as early as 16 years in. That
tiny 1% difference has a massive impact
on your risk. And visually, the danger
is even more stark. Remember that chart
with the red failure clusters for the 5%
rate? This is the same chart, but for a
6% rate. Just look at all that extra
red. The clusters of failure get so much
bigger and they trap even more
retirement start years. It is a powerful
picture of how quickly your margin of
safety can disappear. So, the ultimate
takeaway here is this. Retirement
planning cannot be a set it and forget
it strategy. The whole idea of one magic
number is a myth. The real key to
success is staying aware of the economic
conditions, especially those real
returns, and being flexible enough to
adapt your plan when you have to. You
know, we've spent all this time focused
on that scary 10% of cases that ended in
failure. But that begs one final really
fascinating question. If bad timing can
lead to ruin, what does good timing lead
to? What happened to the portfolios that
started in the very best years in
history?