The single decision that will do most to determine your outcome is not which fund you buy. It is what percentage of your money sits in stocks versus everything else.
The stock-bond mix explains the overwhelming majority of the variation in a portfolio’s returns over time — far more than security selection or timing. Age-based rules like “110 minus your age in equities” are a starting point, but goal-based allocation is better: match each pot of money to when you need it. Three common educational models are 90/10 aggressive, 70/30 balanced and 50/50 conservative. Asset-allocation ETFs deliver any of these globally diversified and automatically rebalanced in one holding, at around 0.20%.
The finding usually credited to Brinson and colleagues is that the great majority of the variation in a portfolio's returns over time is explained by its asset allocation policy, rather than by which specific securities were chosen or when they were bought.
The result is frequently overstated — it is a statement about variability over time for institutional portfolios, not a claim that "allocation determines 90% of your return." But the practical conclusion survives the nuance intact: the stock-versus-bond decision matters more than any decision you make inside those categories.
The intuition is straightforward. A portfolio 90% in equities and one 50% in equities will behave completely differently in any given year, regardless of which equity fund each one holds. In 2008, the difference between two global equity funds was a few percentage points; the difference between 90% and 50% equity exposure was enormous. Choosing between two similar index funds is a decision worth a few basis points. Choosing your equity weight is worth tens of percentage points of drawdown.
Most new investors spend their attention on the smallest decision available — which specific fund to buy — and treat the allocation as an afterthought. Reverse that. Decide your equity percentage carefully, based on horizon and on what you would genuinely hold through a 35% decline, then implement it with any reasonable low-cost fund. The first decision is worth a hundred times the second.
The classic heuristic is "100 minus your age" in equities, updated by many to 110 or 120 minus your age to reflect longer lifespans and lower bond yields. A 35-year-old would hold 75–85% equities; a 65-year-old 45–55%.
It is a reasonable starting point and it gets one important thing right: equity exposure should generally fall as your horizon shortens. But it has real limitations:
Goal-based allocation is the better frame: split your money by when you need it, and allocate each pot to its own horizon. Emergency fund → cash. Down payment in two years → cash or GIC. Retirement in 25 years → equity-heavy. Your "overall allocation" then falls out as a result rather than being chosen in the abstract.
These are educational illustrations of how allocation changes the experience of owning a portfolio, not recommendations. The drawdown figures are approximate historical magnitudes for globally diversified portfolios in severe bear markets.
| Model | Stocks / bonds | Typical expected real return | Rough worst-case decline | Suits |
|---|---|---|---|---|
| Aggressive | 90 / 10 | ~5% | −40% or worse | Long horizons, stable income, proven tolerance |
| Balanced | 70 / 30 | ~4% | ~−30% | The common default for mid-career accumulation |
| Conservative | 50 / 50 | ~3% | ~−20% | Near or in retirement, or low tolerance |
The important line in that table is the drawdown column, not the return column. Everyone wants 90/10 when they read the expected return. The question that decides your allocation is the other one: if this portfolio fell 40% and stayed there for two years, would I keep contributing? If the honest answer is no, 90/10 is the wrong allocation for you regardless of your age, because the return you actually get is the return of the portfolio you hold, not the one you started with.
Since 2018, Canadian investors have had access to asset-allocation ETFs — single funds that hold a globally diversified stock-and-bond portfolio at a fixed target allocation and rebalance themselves automatically. Vanguard and BlackRock's iShares both offer a family; other providers have followed.
They come in tiers by equity weight — typically 100%, 80/20, 60/40 and 40/60 — and a single purchase gives you:
This is the option many Canadian self-directed investors choose, and the reason is behavioural as much as financial. A portfolio of six ETFs requires you to decide what to buy each month and to rebalance periodically — six recurring opportunities to tinker. A one-ticket fund requires you to buy the same thing every month forever. The gap between what a portfolio returns and what its owner receives (Lesson 1.4) narrows considerably when there are no decisions left to get wrong.
The Couch Potato approach — buy a fixed, diversified allocation, add money on schedule, rebalance occasionally, ignore forecasts — long predates these funds. What the one-ticket ETF did was compress the whole strategy into a single line item, which removed the last practical excuse for not doing it.
Rules like “110 minus your age in equities” are a reasonable starting point — 75–85% equities at 35, around 50% at 65. But they ignore your goal, your other assets, and your income stability. A better approach is goal-based: match each pot of money to when you will need it, so an emergency fund sits in cash and retirement money 25 years out sits mostly in equities. Then sanity-check the result against what you would genuinely hold through a 35% decline.
For most Canadian self-directed investors, yes. A single purchase gives global diversification across thousands of securities plus automatic rebalancing, at roughly 0.20% a year. You pay perhaps 0.10% more than assembling the same exposure yourself, and in exchange you remove every recurring decision — which is where most investors actually lose money. The main reasons to build it yourself are a large taxable account, where US withholding tax treatment differs, or a genuine need for a non-standard allocation.
Model the same contributions under an aggressive and a conservative return assumption. The gap is what the allocation decision is worth — and it is far larger than any fund choice you will make.
Educational purposes only — not financial, investment or tax advice. RiskStock is not a registered dealer, adviser, or tax professional. Nothing in this course is a recommendation to buy or sell any security or product. Tax and benefit figures are for the 2026 tax year, were verified against official sources on 2026-07-27, and change annually — confirm your own numbers with the CRA and a qualified professional before acting.