Rolling Returns vs Point-to-Point: Judging a Fund's Consistency
A '5-year return' is one lucky — or unlucky — window. Rolling returns measure every window at once, separating a consistent fund from a fortunate one.
Open almost any fund brochure and one number leads the page: the 5-year return. It looks authoritative — half a decade of evidence, distilled to a single percentage. But that number is far more fragile than it appears, and learning why is the difference between picking a steady fund and picking a lucky one.
A trailing “5-year return” is a single point-to-point measurement. It compares the fund’s NAV today against its NAV exactly five years ago, then annualises the gap. That’s it — two prices, two dates. Everything that happened in between is invisible, and the result is held hostage by its two endpoints.
One number, two dates, lots of luck
Here is the uncomfortable part. Shift the start date by just a few months and the same fund can report a wildly different five-year number. Begin the window near a market bottom and the NAV five years ago was depressed, so the climb out flatters the return. Begin it near a peak and the starting NAV was inflated, so the same fund looks mediocre. The portfolio didn’t change. The manager didn’t change. Only the dates did.
This is start-date luck, and it cuts both ways. The fund that happens to have a market low sitting five years behind it gets to advertise a glittering figure it did nothing to earn. A genuinely excellent fund whose window opens near a peak can look ordinary on the same brochure.
| 5-year window | Annualised return |
|---|---|
| Started near a market low | 19% |
| Started near a market high | 8% |
| Rolling median (every window) | 13% |
Illustrative 5-year annualised returns. Real figures vary by fund and period; the point is the spread, not the values.
Same fund, same five-year length — but a window that began near a low shows 19% a year, while one that began near a high shows 8%. Both are honest point-to-point numbers. Either could be the one printed in a factsheet, depending entirely on the calendar. So which is the real fund? Neither, on its own.
Rolling returns measure every window
Rolling returns fix the problem by refusing to pick a single window. Instead of measuring NAV-today against NAV-five-years-ago once, you compute the five-year return for every possible window across the fund’s history — rolling the start date forward day by day — and then summarise the whole set. The median tells you the typical outcome; the best and worst mark the range; the share of windows that finished positive tells you how often the fund actually delivered.
That single snapshot becomes a distribution. And a distribution is what reveals a fund’s character. A high median with a narrow spread means the fund returned roughly the same whenever you happened to start — genuine consistency. A high headline number sitting on top of a wide spread means the result swung hard depending on timing — volatile, or simply fortunate. Two funds can advertise the identical trailing 5-year figure while one was a steady escalator and the other a rollercoaster; only the rolling view tells them apart.
In the illustrative table above, the rolling median of 13% is the honest answer the two cherry-picked endpoints were arguing over. It’s what the fund tended to return, not what it returned once.
How to read it
The practical shift is small but powerful: judge a fund by its rolling median and its spread — and the percentage of positive windows — rather than by the single trailing number a brochure leads with. One asks what did this return on one particular day; the other asks what does this tend to return. Only the second question is answerable with any confidence.
The fund pages here are built for exactly this. Browse Funds and each detail page surfaces rolling-return summaries alongside the headline figures, and Compare Funds lets you put two schemes side by side so the difference between a steady median and a wide one is visible at a glance. Our study on whether active large-cap funds actually beat the index leans on these rolling-window histories too — there, to weed out funds that don’t yet have a genuine ten-year record before judging any of them. It’s a working reminder that a single headline figure is rarely the whole story.
A trailing return is one frame from a long film. Rolling returns play the whole reel — and a fund you’d judge on consistency deserves to be watched, not photographed.