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

Warren Buffett's final lesson

I’ve long seen Buffett as a flawed genius: a great investor though a man with shortcomings. With his final letter to Berkshire shareholders, I reflect on how my views of Buffett have changed and the legacy he leaves.

The housing market is heading into choppy waters

With rates on hold and housing demand strong, lenders are pushing boundaries. As risky products return, borrowers should be cautious and not let clever marketing cloud their judgment.

Why it’s time to ditch the retirement journey

Retirement isn’t a clean financial arc. Income shocks, health costs and family pressures hit at random, exposing the limits of age-based planning and the myth of a predictable “retirement journey".

Australia's retirement system works brilliantly for some - but not all

The superannuation system has succeeded brilliantly at what it was designed to do: accumulate wealth during working lives. The next challenge is meeting members’ diverse needs in retirement. 

The 3 biggest residential property myths

I am a professional real estate investor who hears a lot of opinions rather than facts from so-called experts on the topic of property. Here are the largest myths when it comes to Australia’s biggest asset class.

Welcome to Firstlinks Edition 637 with weekend update

What should you do if you think this market is grossly overvalued? While it’s impossible to predict the future, it is possible to prepare, and here are three tips on how to best construct your portfolio for what’s ahead.

  • 13 November 2025

Latest Updates

Investment strategies

Australian stocks will crush housing over the next decade, 2025 edition

Two years ago, I wrote an article suggesting that the odds favoured ASX shares easily outperforming residential property over the next decade. Here’s an update on where things stand today.

Property versus shares - a practical guide for investors

I’ve been comparing property and shares for decades and while both have their place, the differences are stark. When tax, costs, and liquidity are weighed, property looks less compelling than its reputation suggests.

Investment strategies

What if Trump is right?

Trump may be right on two trends: nations are shifting from aspiration to essentials and from global dependence to self-reliance, pushing capital toward security, infrastructure, and energy.

Gold

After a stellar 2025, can gold shine again next year?

Gold has had a remarkable 2025, with the spot price likely to post its strongest return since 1971. This explores the key factors that will shape the outlook for the yellow metal next year, and long-term.

Superannuation

Critics of Commonwealth defined benefit schemes have it wrong

Critics like Clime's John Abernethy have questioned many aspects of defined benefit pensions for public servants. This is an attempted rebuttal, suggesting these pensions aren't the problem they're made out to be.

Infrastructure

Why airport stocks deserve a place in long-term portfolios

Aircraft constraints are holding back global air travel. Those constraints should soon ease which combined with a structural boom in travel demand could be a boon for global airport stocks.

Investment strategies

What is the future of search in the age of AI?

Search is changing fast. AI tools like ChatGPT and Google’s Gemini are reshaping how we find information, opening new opportunities for innovation, user engagement, and future revenue growth.

Sponsors

Alliances

© 2025 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.