Calculator
Asset Allocation — Broad Portfolio Calculator
Asset Allocation — Broad Portfolio Calculator
Expected Annual Return
6.8%
Portfolio Analysis
A balanced mix with 75% in stocks expects about 6.8% annually with 12.0% volatility — moderate growth with meaningful ballast from bonds and alternatives. This profile historically limits peak drawdowns to roughly half of an all-equity decline while keeping decent long-term compounding.
Expected returns, volatilities, and correlations are long-run historical estimates and assumptions, not forecasts. Real outcomes vary widely and past performance does not guarantee future results. Educational only, not investment advice.
Building an Allocation Across Six Asset Classes
Asset allocation — the decision of how much to hold in each major asset class — is the largest single driver of a portfolio's returns and risk. Academic research, most famously the Brinson, Hood, and Beebower studies, found that allocation policy explains the majority of a portfolio's return variability over time, far more than individual security selection or market timing. This calculator models a broad six-class portfolio — Australian shares, international shares, bonds, listed property (A-REITs), commodities, and cash — the same building blocks used by target-date options in Australian super funds, endowments, and most robo-advisors. The practical reason Australians obsess over allocation is that it encodes their risk tolerance, time horizon, and goals into a single set of percentages, and it is the number one lever they actually control after joining super. An aggressive 85/15 equity split suits a 25-year-old with decades until preservation age, while a retiree drawing a pension may anchor on bonds and cash. The hard part is that expected return and risk trade off: more shares mean more compounding power but deeper drawdowns in bad years. By estimating both the expected return and the volatility of any six-class mix, this tool makes that trade-off visible so you can choose a portfolio you can actually live with — including the home bias to ASX shares that most Australian investors carry.
Expected Return and Portfolio Risk
The expected portfolio return is the weighted average of each class's expected return: multiply each class weight by its assumed long-run return and sum the results. The assumptions used here are conservative long-run nominal estimates: Australian shares 7.5%, international shares 8%, bonds 4%, listed property 7%, commodities 5%, and cash 3%. Portfolio risk requires more care because assets move together. The volatility formula sums each pair of classes: Weight1 × Weight2 × Vol1 × Vol2 × Correlation, where correlations describe how classes move relative to one another. The model uses conservative correlations: Australian and international shares move closely together (about 0.85), shares and bonds are negatively correlated, A-REITs track shares at about 0.7 correlation, commodities show low correlation to equities, and cash is uncorrelated. The square root of that total is the portfolio's estimated annual volatility. The tool also projects the future value of your initial investment at the expected return over your horizon. Diversification shows up directly in the math: adding weakly correlated assets lowers volatility by more than it lowers expected return — the free lunch at the heart of broad portfolio design, and the reason global diversification softens the well-documented ASX concentration.
Expert Insights
Allocation Is the Decision; Stock Picking Is the Detail
Brinson's research and decades of fund data show the share/bond split explains most return differences between investors. Getting your equity weight right for your horizon and stomach matters more than any single fund or stock choice — it matters more than whether you hold Vanguard, BlackRock, or a home-grown ASX-listed ETF. Most portfolio mistakes are allocation mistakes dressed up as selection mistakes.
The Equity Weight Is Really a Drawdown Dial
A portfolio's worst years scale roughly with its share weight: all-share fell about half in 2008–09, a 60/40 mix about 25–30%, and a 40/60 mix roughly half that again. The ASX fell more than a third in the March 2020 crash alone. If you cannot stomach a 40% peak-to-trough decline, you should not run an all-equity portfolio regardless of how high the expected return looks here — the drawdown dial is the honest way to read your equity allocation.
Home Bias Is Real — and So Is Its Cost
Australian investors hold far more domestic shares than the ASX's roughly 2% weight in global markets would justify, chasing franking credits and familiar names. Franking is genuinely valuable, but an all-ASX portfolio concentrates risk in financials and miners and forgoes global growth engines. This calculator's expected return barely changes between a 30% and 70% home share, while diversification into international shares lowers volatility — evidence you can blend franking benefits with global diversification rather than choosing one.
Actionable Tips
- 1
Start From Your Time Horizon, Not Your Optimism
A common rule of thumb: money needed within 5 years belongs in cash and short bonds; 5 to 10 years in a balanced mix; 10+ years can tolerate a heavy equity tilt. Set your equity weight by when you need the money — remembering super money is locked until preservation age — then use this calculator to see the risk and return that choice implies.
- 2
Implement Simply With a Few Low-Cost Funds
Each class here maps to an index fund: an ASX 300 or ASX 200 fund, a global shares fund (hedged or unhedged), a composite or government bond fund, an A-REIT fund, a commodities ETF, and a high-interest cash account. You can build this exact allocation with three to six funds at an average cost of a few basis points, which is more than half the battle won.
- 3
Rebalance Annually, Not Emotionally
Set your percentages, then rebalance back to them once a year or when any class drifts more than 5 percentage points. Rebalancing forces you to trim winners and buy laggards mechanically, removing emotion from the equation — and inside super, switching between options is typically free of brokerage and CGT events. It is the single most reliable discipline this allocation demands.
Real-World Examples
Kayla Picked a Volatility She Could Sleep With
Kayla, 32, wanted maximum growth but froze during a 20% market drop on her old all-share portfolio. She used this tool to test a 70% equity mix and saw volatility drop from about 15% to 11% while expected return fell only modestly. She has stuck with the 70/30 blend since, because she now believes she can hold it through the next crash — the behavioural win matters more than the half percent of expected return she gave up.
Robert Built a Retirement Glidepath
Robert, 58, modelled three allocations for the decade before he could access super: an 80/20 mix, a 60/40, and a conservative 40/60. The expected-return gap between the aggressive and balanced options was small, but the volatility gap was large. He chose the 60/40, planning to shift further conservative in his final working years rather than gamble the runway — the same logic Australian super funds bake into their lifecycle options.
The Patels Found Diversification Was Not Free Lunch
The Patels added international shares, A-REITs, and gold to a total-market ASX portfolio, expecting higher returns. The calculator showed the additions mainly lowered volatility and slightly trimmed expected return. They kept a modest international and A-REIT sleeve for resilience but dropped the gold, understanding they had bought insurance, not extra growth — and that the franking credits on their ASX core still did the heavy lifting on after-tax income.
Glossary of Terms
- Asset Allocation
- The division of a portfolio among major asset classes such as shares, bonds, listed property, and cash.
- Correlation
- A measure from -1 to +1 of how closely two assets' returns move together; low correlation between holdings improves diversification.
- Volatility
- The typical size of a portfolio's year-to-year swings — the standard statistical measure of risk, expressed as annualised standard deviation.
Frequently Asked Questions
Everything you need to know about this topic.
Ivy Sinclair-Wren
Financial Chaos Analyst
Ivy Sinclair-Wren is a Financial Chaos Analyst covering investing, AI, wealth psychology, and the emotional consequences of opening finance apps during market crashes. Based in Melbourne, she specializes in demystifying the Australian tax code and helping users navigate the intersection of spreadsheet logic and human irrationality.