Why Diversification Matters: Missing the Market’s Winners
Justin D. Caldwell - Sep 09, 2026
Steady Gains #13 · September 2026
A reminder about our September 23 webinar, the cost of missing the market’s winners, and a simple way to help us coordinate with your accountant.
This month’s webinar
The Evidence-Based Portfolio: How We Invest and Why
Wednesday, September 23, 2026 · 12:00 PM ET · Virtual
In our last edition, we looked at the evidence behind our investment approach. On September 23, we’ll walk through how we put it into practice.
We’ll cover:
- How we build portfolios. What we own, why we diversify globally, the tilts we make, and the role of bonds.
- How we manage them around your needs. Funding withdrawals, rebalancing, and keeping your portfolio aligned with your financial plan.
- What these decisions can be worth. Illustrations of the difference lower turnover, thoughtful account placement, and lower investment costs can make over ten and twenty-five years.
We’ve set aside an hour: 45 minutes for the presentation, followed by time for questions.
Friends and family are welcome, including anyone who would like a clearer understanding of our approach to investing.
Can't attend live? Register anyway and we'll send you the recording.
A preview: the cost of missing the winners
Diversification is usually explained as protection against the investments that go wrong. It does something else as well. It gives us a better chance of owning the ones that go extraordinarily right.
A small number of companies drive a large share of the market’s return over time. Over the fifteen years to the end of 2025, the MSCI All Country World Index returned 10.4% a year. In an illustration removing each year’s ten largest contributors, that annualized return falls to 7.2%. Remove each year’s top twenty-five and it falls to 5.8%.
No investor sets out to exclude the best-performing companies. That can happen simply by holding thirty companies instead of three thousand. A concentrated portfolio has to decide what to leave out, and it has to decide before knowing which businesses will matter. Every name left out is a name that might have been one of the ten.
We own broadly to reduce that risk. We want to participate in the next exceptional performer’s success without having to name it first.
Source: Dimensional, “Benefits of Diversification,” using Bloomberg data. MSCI ACWI with gross dividends, 2011–2025, U.S. dollars. Annualized returns; exclusions are hypothetical.
Keeping Your Accountant in the Loop
Some investment and tax-planning decisions benefit from a conversation before year-end. Your accountant has a view of your tax situation beyond the accounts we manage, and sharing information can help bring those pieces together.
When your accountant needs details for a return or information about a transaction, having your consent on file makes it easier for us to provide the relevant account information.
The short form below captures your accountant’s details and your authorization to share information.
Consent to Connect with Your Accountant
If we already have your authorization, please let us know if your accountant’s contact details have changed.
Team Update: September 9, Twice
Sarah Morgan and David Broderick share a September 9 birthday—a coincidence we discovered while looking at the calendar.
We marked the occasion with macarons baked by David’s daughter. Happy birthday to both, and thank you to our baker!
Justin D. Caldwell, CIM®
Senior Investment Advisor, Portfolio Manager
Caldwell Group · Richardson Wealth Limited
Enjoyed this edition? Subscribe to Steady Gains.
The opinions expressed in this report are the opinions of the author and readers should not assume they reflect the opinions or recommendations of Richardson Wealth Limited or its affiliates. Assumptions, opinions and estimates constitute the author’s judgment as of the date of this material and are subject to change without notice. We do not warrant the completeness or accuracy of this material, and it should not be relied upon as such. Before acting on any recommendation, you should consider whether it is suitable for your particular circumstances and, if necessary, seek professional advice. Past performance is not indicative of future results. Insurance Services are offered through Richardson Wealth Insurance Services Limited (RWISL) in BC, AB, SK, MB, NWT, ON, QC, NB, NS, NL and PEI. Insurance products are not covered by the Canadian Investor Protection Fund (CIPF). RWISL is a wholly-owned subsidiary of Richardson Wealth Limited (RWL). RWL is a subsidiary of iA Financial Corporation Inc. and is not affiliated with James Richardson & Sons, Limited (JRSL). Richardson Wealth is a trademark of JRSL and RWL and its subsidiaries are licensed users of the mark. RWL is a member of CIPF.