Key points (as at Q3 2026)
- A 1-year return is a rolling 12-month window. Both ends move, so the figure can change sharply while the fund itself has an ordinary month.
- In 2026 this happened across the ASX: several funds' trailing figures halved or flipped negative as boom months rolled out of the window. Past performance is not a reliable indicator of future returns.
- 3 and 5-year figures are annualised compound rates, not totals, and smooth the noise a 1-year window amplifies.
- No trailing window, long or short, forecasts anything. Every figure here describes the past.
Last updated: Q3 2026. Figures are computed from ETFLens data as at Q3 2026, sourced from issuer disclosure documents and refreshed quarterly. Past performance is not a reliable indicator of future returns.
Every ETF page on the internet shows a 1-year return, and almost none of them explain what the number actually is. It is not a rating, not a speed, and definitely not a forecast. It is a photograph of one specific 12-month window, and the window moves every day. Understanding that single fact explains most of the confusing things trailing returns do, including the one that catches investors most often: the number changing dramatically while the fund does almost nothing.
The rolling window
A 1-year return measures total performance, price movement plus distributions reinvested, over the 12 months ending at the stated date. Next quarter, the window slides forward: three new months enter and three old months leave. If the months that left were exceptional, the new figure drops regardless of what the fund did lately. If terrible months roll out, the figure jumps.
2026 has been a live demonstration. As at Q3 2026, the Nasdaq-100 fund NDQ shows a 1-year return of approximately 11.7%, roughly half what its trailing figure showed earlier in the year, and the global uranium fund URNM shows approximately 11.3% after its trailing figure spent part of the year above 80% while a historic boom year sat inside the window. Past performance is not a reliable indicator of future returns. In both cases the driver was the window, not a crash: powerful months from 2025 rolled out of the calculation, and the arithmetic followed.
Base effects: the year-ago month matters as much as this one
Statisticians call this a base effect. The start of the window is the base the return is measured from, and when the base was unusually low, the trailing return looks spectacular; when the base was unusually high, it looks poor. Neither says much about the fund today.
It also runs in reverse. A fund can post a negative 1-year figure while quietly recovering for months, simply because the window still contains the fall. As at Q3 2026, the Australian momentum fund MTUM shows a 1-year return of approximately -5.2%, a figure that describes the whole window, not its most recent months. Past performance is not a reliable indicator of future returns, in either direction.
1-year totals vs annualised figures
The 3 and 5-year figures on ETF pages are not totals: they are compound annual rates, the steady yearly percentage that would produce the same end value. That makes long and short windows directly comparable, and it is why they often disagree. As at Q3 2026, NDQ's 1-year figure of approximately 11.7% sits below its 3-year rate of approximately 20.0% p.a.: a soft recent 12 months inside a strong 3-year stretch. The gold miners fund MNRS shows the reverse shape, a 1-year figure of approximately 43.7% above its 5-year rate of approximately 16.8% p.a., a recent surge against a more ordinary half-decade. Past performance is not a reliable indicator of future returns; the comparison tells you where the strength sat in time, nothing about where it goes next.
Why single-theme funds swing hardest
Scan any 12-month return table and the extremes, top and bottom, are usually thematic funds. Concentration is the reason: one theme, one commodity or one sector drives the whole portfolio, so the fund inherits that story's full volatility. A broad fund like IVV, approximately 9.4% over the past year as at Q3 2026, spreads across hundreds of companies whose individual swings partly cancel. Past performance is not a reliable indicator of future returns. The same concentration that produces an 80% trailing year in a boom produces the mirror image after it, which is worth remembering before treating any table-topping figure as a signal.
What a return figure cannot tell you
A trailing return cannot tell you what happens next, whether the conditions that produced it still exist, or whether a fund is well built. It also says nothing about your own entry point: an investor who bought partway through the window experienced a different result from the published figure. Returns are one input for understanding what a fund did, alongside fees, holdings, concentration and structure, all of which ETFLens shows on each fund page and side by side on the compare tool. Selecting funds by last year's table position is one of the most consistently punished habits in investing, which is a statement about how windows work, not advice about any fund.
How ETFLens computes the figures
Return figures on ETFLens come from issuer disclosure documents, are refreshed quarterly, and carry the data vintage on every page, currently Q3 2026 for the funds named here. Figures are shown as published by issuers: 1-year figures as 12-month totals, 3 and 5-year figures as annualised rates. Every figure in this guide is computed live from the same dataset, so the examples above update as the windows roll, which is rather the point.
This article is general information only and not personal financial or tax advice. ETFLens does not hold an Australian Financial Services Licence (AFSL). Tax outcomes depend on your individual circumstances; consider a registered tax agent. Consider your own objectives, financial situation and needs, or speak with a licensed financial adviser before making investment decisions. Past performance is not a reliable indicator of future returns.