The 7% Property Growth Myth: What 12 Years of Real Australian Price Data Shows, State by State

“Australian property grows about 7% a year and doubles every ten years.” You’ll hear it from agents, brokers, and half the forums online. It’s the assumption baked into most spreadsheets, most “what your property could be worth” calculators, and most retirement plans built on the back of a napkin.

It’s also wrong almost everywhere.

Heyward measured the 10-year growth rate of 30 of Australia’s most-targeted investor markets — every state and territory, capital-city CBDs through to regional centres — across 12 years of price data (2014–2025). In five of the seven states with enough coverage, the real number came in below 7%. In most, well below. The “doubles every decade” rule held in exactly one state.

This isn’t a rounding error. Modelled over ten years, the gap between “7%” and the actual rate is hundreds of thousands of dollars on a single property — the difference between a retirement plan that works and one that quietly doesn’t.

Here is what 12 years of data actually shows, state by state. And because a national average is nearly as useless as the 7% myth itself, the second half is the part that matters most: how to find the real growth rate for the specific suburb you’re looking at.

“Doubles every ten years” is the rule of 72 run backwards: to double a number in ten years it has to compound at about 7.2% a year. That’s where the round “7%” comes from. It isn’t a law of physics. It’s a tidy approximation of a multi-decade national average — and three things make it useless for the property you’re actually evaluating.

It’s a national number, and Australia isn’t one market. It’s dozens of markets on different cycles. A national average is the average of Sydney’s CBD crawling along at 1.1% a year and Maroochydore running at 9.45% — a single figure that accurately describes neither of them. Averaging a flat market and a boom market gives you a number that exists nowhere on the map.

It’s dragged up by specific past booms. The long-run national figure leans on particular periods — the early-2000s surge, the 2013–2017 Sydney/Melbourne run, the 2020–2022 pandemic spike. Bake those into a forward assumption and you’re quietly forecasting that the last boom repeats on schedule. The decade we measured (2014–2025) contained a boom, a correction, a pandemic spike and a rate-hike squeeze — a fuller, more honest cycle than any single boom window.

It’s nominal. The 7% rule never mentions inflation. Over our window, inflation ran in the mid-single digits at its peak and around 2.5–3% on average (per RBA figures). A suburb compounding at 3.5% nominal is barely above water once you take inflation out — a fact the 7% story never has to confront.

The 7% myth survives because it’s convenient: round, optimistic, and it helps sell property. None of those are reasons to model your future on it.

Here are the state-level averages from our 30-market sample — the compound annual growth rate over the period, blending houses and units:

(The Northern Territory is set aside throughout this piece — our coverage there is a single market, Darwin, at −1.75% a year, too thin to treat as a state read. More on thin data in §05.)

Six of the seven states grew slower than 7%. Five of them grew slower than 6%. Only Tasmania — riding the Hobart affordability catch-up — beat the rule the entire country supposedly follows. (Zoom in on the capitals themselves and the ranking inverts the hype: the biggest, most-talked-about capitals grew the slowest.)

Put the doubling claim to the test directly. At New South Wales’ measured 3.7% a year, the rule of 72 says a property doubles in about 19 years, not ten. “Doubles every decade” in NSW is really “doubles every two.”

And the gap isn’t academic — it’s a forecasting error you can price. Take a $700,000 property and run it forward ten years:

At the 7% myth:        $700,000 × 1.07¹⁰   = $1,377,000
At NSW's real 3.74%:   $700,000 × 1.0374¹⁰ = $1,011,000
                                    ─────────────────────
Forecasting gap on ONE property:              $366,000

At Victoria’s 3.5% it’s worse — the same property reaches about $986,000, a $391,000 gap versus the myth. That’s not a margin-of-error wobble. It’s a quarter of a property, invented by a spreadsheet assumption, on a single line of a plan that might have ten lines.

Here’s the part that catches even careful investors: fixing “7%” with a state average isn’t enough, because the variation within a state is wider than the variation between states.

Look inside Victoria. Our slowest market and our second-fastest both sit in greater Melbourne, both measured over the same 12 years:

• Richmond: 0.8% a year. Inner-city, unit-heavy, flat for a decade.
• Frankston: 6.25% a year. Outer bayside, houses, an affordability-driven run.

That’s nearly an 8× difference in the rate of compounding inside one capital city. “Victoria grew 3.5%” is true — and it describes neither suburb.

New South Wales tells the same story:

• Sydney CBD: 1.1% a year versus Newcastle: 5.25% a year.
• Parramatta: 2.55% versus Penrith: 5.1% — two Western Sydney markets, a 2× gap.

And Queensland holds the widest pair in the whole sample: Brisbane City at 1.3% against Maroochydore at 9.45% — same state, same decade, a sevenfold difference in annual growth.

The lesson is blunt. The state number is more honest than the national one, but it still hides the only number that affects your return: the specific suburb’s. A “5% state” is a coin-flip between a 1% suburb and a 9% suburb, and which one you buy decides whether the plan works.

The 7% assumption doesn’t just overstate a future price. It compounds into a wrong plan — a retirement date that arrives years later than the spreadsheet promised.

Take an investor holding that same $700,000 property for 15 years as part of a portfolio meant to fund retirement:

At the 7% myth:        $700,000 × 1.07¹⁵   = $1,931,000
At NSW's real 3.74%:   $700,000 × 1.0374¹⁵ = $1,214,000
                                    ─────────────────────
Equity that never arrives:                    $717,000

$717,000 of equity that the myth promised and the market never delivered — on one property. The investor who modelled at 7% borrowed against it, planned their exit around it, and set a retirement year on the strength of it. The market hands back a number 37% smaller, and the freedom year slides out with it.

This is exactly why how many investment properties you actually need to retire is so sensitive to the growth rate you assume. Get the rate wrong by three points and you don’t need a slightly bigger portfolio — you need a materially bigger one, or several more years. The myth doesn’t make you a little optimistic. It quietly moves your finish line.

The asymmetry is what makes it dangerous. Assume 7% and the failure mode is over-borrowing, over-paying, and retiring late when the growth doesn’t show. Assume 3.5% and the worst case is that you’re pleasantly surprised. There’s only one of those mistakes you want to make.

The fix isn’t a better national number. It’s the suburb’s own number. Here’s the method — the same workup Heyward runs on every property in a watch list.

Step 1 — Pull the long-run median history. Get 10–12 years of median sale prices for the specific suburb, by property type. Your state’s valuer-general or land-titles office publishes historical sales; the major portals show suburb median trends; some councils publish their own series. Ten years is the minimum that survives a single cycle — three years of data tells you about the last boom, not the long run.

Step 2 — Compute the CAGR yourself. Don’t trust a “+44% over the decade” headline — annualise it. The formula is one line:

CAGR = (latest median ÷ earliest median) ^ (1 ÷ years) − 1

Worked example — a suburb's house median, $500,000 (2014) → $720,000 (2024):
  (720,000 ÷ 500,000) ^ (1 ÷ 10) − 1
  = 1.44 ^ 0.1 − 1
  = 1.037 − 1
  = 3.7% a year

That “44% rise” is a perfectly ordinary 3.7% a year — below the myth, and exactly the kind of number that gets dressed up as a boom in a sales brochure.

Step 3 — Split houses and units. They diverge, often violently. Inner-city unit markets sat flat or fell across our window while houses in the same postcode ran; a blended median hides it. If you’re buying a unit, the house trend is marketing, not evidence.

Step 4 — Take inflation out. A 3.5% nominal suburb, against ~2.5–3% average inflation over the period, grew barely 1% a year in real terms. Nominal growth is what you’ll see quoted; real growth is what actually builds wealth. Subtract one from the other before you get excited.

Step 5 — Distrust thin data. A suburb with a handful of sales a year has a median that one unusual transaction can swing five percent. CBD postcodes are the worst offenders — Sydney’s CBD is units-only (no houses transact), Brisbane City and Melbourne CBD are noisy, and our entire Northern Territory read rests on one market. If the sale count is low, widen your window, blend neighbouring suburbs, or treat the number as a hint rather than a fact. Never anchor a 30-year plan on a five-sale-a-year suburb.

Step 6 — Then look past price. A past CAGR is history, not a guarantee. The forward signals — vacancy trends, who’s actually moving in, and infrastructure that’s funded rather than announced — are what tell you whether the next decade rhymes with the last. Those each deserve their own guide; the discipline that ties them together is refusing to assume.

Stop modelling at 7%. Three rules replace it:

1. Use the suburb’s measured rate where you can get clean, deep-enough data.
2. Default to a conservative band where you can’t — for most established capital-city markets, 3–4% nominal is closer to the long-run truth than 7%.
3. Stress-test below your assumption, always. Run the plan at your number minus two points and ask whether it still works. If it only works at 7%, it doesn’t work.

A growth rate isn’t a detail in a property model. It’s the lever the whole forecast swings on — and it’s the one number the market is most happy to let you guess wrong, because the optimistic guess is the one that gets the deal done.