Register For Our Mailing List

Register to receive our free weekly newsletter including editorials.

Why Australia has missed out on the “small cap effect”

Introduction

The idea that smaller companies offer higher risk-adjusted returns than larger companies, a claimed phenomenon known as the “small cap effect,” continues to live rent-free in the collective mind of Australian investors.

The size effect was first coined in Rolf W. Banz’s seminal 1981 paper “The relationship between return and market value of common stocks.” 1 Banz asserted that smaller firms, which he defined as the smallest 20% of the universe by market capitalisation, have higher risk adjusted returns, on average, than larger firms. Banz also found little difference in returns between medium sized and large sized firms.

But, for an investor, is the concept all it’s cracked up to be? Namely, does Banz’s concept of the small cap effect hold water in the Australian market?

There are currently 2,400 firms listed in the ASX. If an index was to be created on the ASX using Banz’s definition of a small firm, the largest constituent would be roughly A$8m in market capitalisation. In contrast, the smallest company in the ASX small ordinaries index currently is $200m in market capitalisation; and some of the largest constituents are larger than A$10b in market capitalisation. Perhaps unsurprisingly, the experience of an in investor in the ASX small ordinaries index has persistently bore no resemblance to the stellar returns depicted by Banz.

While many investors in Australia take a decision to structurally overweight small cap stocks given the sector and stock concentration in the large cap index, our analysis suggests that a separate allocation to small caps isn’t necessarily the best or most cost effective way to achieve this.

This paper will make the case that the performance, risk and constituent characteristics of the small cap index in Australia are poor; that the small cap designation is itself a misnomer (at least as it pertains to Australia); and the consequent benefit of investing in an unconstrained fund that can play the entire ASX.

Download the full paper

  •   13 June 2024
  • 1
  •      
  •   
banner

Most viewed in recent weeks

The strange effect of the 30% minimum capital gains tax

The 30% minimum tax on capital gains sits at the heart of the budget's proposed reforms. Yet the mechanics reveal anomalies that introduce unexpected distortions that raise questions about its design.

Does your will qualify for the discretionary testamentary trust exemption?

Treasury has confirmed the exemption many families were hoping for. But buried in the fine print are two conditions that could leave some wills on the wrong side of the exemption, despite years of careful planning.

Ranking three common retirement strategies

The defining challenge of retirement isn't just about building wealth, it's about converting your lifetime savings into sustainable income. A holistic understanding of different strategies can improve long-term outcomes.

Are you making these SMSF mistakes?

After four decades advising investors, there are a few common mistakes I've seen SMSF investors make. From holding too much cash and chasing yield to overtrading and trusting tips. Are these errors costing you?

Why Australian shares are falling behind the world

Australia’s market boasts a long record of outperformance, but recent results tell a different story. Is the ASX’s lagging performance a temporary setback or evidence that structural forces will keep global markets ahead?

Australia has saved $4.5 trillion for retirement. Here's what matters more

Most Australians approaching retirement can tell you the exact dollar value of their super account. But success depends on more than a sizeable balance. Here's four key questions to ask yourself at the start of the financial year. 

Latest Updates

Investment strategies

UniSuper CIO shares his reflections on the 2025-2026 financial year

Markets climbed a wall of worry in FY26, but artificial intelligence remained the dominant force, rewarding some of the world’s biggest companies while leaving others behind.

Planning

Post-Budget blues? A knee jerk won’t help

Sweeping tax changes are reshaping the investment landscape and many investors are considering major restructures. But before chasing lower tax bills, it's worth asking whether those decisions will strengthen—or undermine your ability to build wealth across generations.

Investment strategies

Is value investing still relevant in today’s stockmarkets?

Is value investing relevant in an age when momentum investing, quant strategies and index funds increasingly dominate markets? It is underappreciated how share price distortions may be creating some of the best opportunities for patient, disciplined investors.

Investment strategies

How to find opportunity in global equities

Australia's concentrated market makes global diversification essential, but breadth alone is not enough. Investors still need a disciplined framework combining business quality, sensible valuation and a credible catalyst.

Gold

What keeps the world’s most patient investors returning to gold

While many investors are asking whether gold has peaked, the world's central banks appear to be asking different questions altogether. Their thinking offers useful insights for long-term investors.

Investment strategies

Don’t underestimate Australia

Investor sentiment towards Australia has turned increasingly gloomy, but the data tells a different story. There are still plenty of reasons to remain optimistic.

Superannuation

Are you making these SMSF mistakes?

After four decades advising investors, there are a few common mistakes I've seen SMSF investors make. From holding too much cash and chasing yield to overtrading and trusting tips. Are these errors costing you?

Sponsors

Alliances

© 2026 Morningstar, Inc. All rights reserved.

Disclaimer
The data, research and opinions provided here are for information purposes; are not an offer to buy or sell a security; and are not warranted to be correct, complete or accurate. Morningstar, its affiliates, and third-party content providers are not responsible for any investment decisions, damages or losses resulting from, or related to, the data and analyses or their use. To the extent any content is general advice, it has been prepared for clients of Morningstar Australasia Pty Ltd (ABN: 95 090 665 544, AFSL: 240892), without reference to your financial objectives, situation or needs. For more information refer to our Financial Services Guide. You should consider the advice in light of these matters and if applicable, the relevant Product Disclosure Statement before making any decision to invest. Past performance does not necessarily indicate a financial product’s future performance. To obtain advice tailored to your situation, contact a professional financial adviser. Articles are current as at date of publication.
This website contains information and opinions provided by third parties. Inclusion of this information does not necessarily represent Morningstar’s positions, strategies or opinions and should not be considered an endorsement by Morningstar.