I have long suspected that savers were not always getting good value from their pension funds. But when my team and I ran the numbers even I was taken aback.

We found the worst-performing funds lost almost all of their investors’ money over five years, but what interests me more is whether any of this will prompt people to actually look at their own pension. Because in my experience most people have no idea what funds they are invested in. Many do not even realise their pension is invested at all.

I am talking about defined-contribution pensions, which you can pay into via a workplace scheme or through a pot you manage yourself. They’re usually invested in a wide range of assets, including lots of different funds, plus less risky options such as cash.

Thanks to automatic enrolment, these schemes are now the backbone of retirement saving for many people. But getting people enrolled was only ever step one. Engagement is the part we have failed at.

In our high-risk fund category, five-year cumulative returns ranged from plus 180 per cent at the top end to nearly minus 99 per cent at the bottom.

Minus ninety-nine per cent.

That is not a gentle underperformance. That is almost total destruction of capital.

For example, if Person A had invested £50,000 in December 2020 into the best-performing fund in our analysis, Aviva’s Ninety One Global Gold Pension, which delivered 180.28 per cent over five years, their pot would have grown to £140,140 by the end of 2025.

If Person B had put the same £50,000 into the worst performer in our data, the Zurich JPM Emerging Europe Equity fund, which lost 98.59 per cent over the same time, they would have been left with £705.

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Both funds sit in the same high-risk category. Both would have been offered to savers with a similar appetite for volatility. The outcomes could not be more different.

Now extend that logic. If those same returns were sustained over 20 years, Person A would be looking at £3,085,590. That is the power of compounding when returns are exceptionally strong. Person B would effectively have nothing left. Two tenths of a penny. Wiped out.

Of course, these are extremes — and in the case of the JPM Emerging Europe Equity the loss is down to the fund being suspended in February 2022 after sanctions were introduced following Russia’s invasion of Ukraine — but they are not hypothetical. While no scheme would be invested in just one fund unless you requested it, they are real funds containing real people’s pension savings.

High-risk funds are typically heavily weighted towards equities. They will be more volatile. That is understood. If you are decades from retirement, you may reasonably accept the bumps along the way.

But a 98.59 per cent loss over five years requires more than patience. It requires starting again.

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Which raises some uncomfortable questions. If someone has left their money sitting in a fund that has lost almost everything, has anyone contacted them? Has anyone explained what has happened, reviewed whether that level of risk is appropriate, or discussed alternatives? Or do statements simply continue to arrive, dense with jargon and benchmarks, reassuring enough on the surface to avoid alarm?

Even in the medium-risk category the picture is sobering. Five-year returns ranged from a 79.81 per cent gain to a 46.31 per cent loss. Nearly half a pension gone in a fund labelled “balanced”.

When savers tick a medium-risk box, do they imagine losing 46 per cent of their money in five years? I doubt it.

The low-risk category showed less dramatic divergence, as you would hope, ranging from growth of 7.17 per cent to a loss of 5.1 per cent over five years. But even a small loss is not just a paper loss. It is five years without meaningful growth. That opportunity cost matters, especially in the earlier decades when compounding is doing the heavy lifting.

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Risk selection is not a box-ticking exercise. Too much risk as you approach retirement and you may not have time to recover from a downturn. Too little risk too early and you limit long-term growth. The difference over decades can be tens of thousands of pounds.

Fees are the other part of the equation. Our figures reflect fund performance, not platform charges. Add higher fees to a poorly performing fund and the damage compounds. I have spoken to savers who assumed their pension was “being looked after”, only to discover years later that weak returns combined with charges had left them far behind where they expected to be.

None of this is a call to panic. Nor is it a suggestion to chase the fund that just topped the table. Past performance is not a guarantee of what comes next.

But it is a very clear prompt.

Check.

Do not assume the default scheme you were placed into years ago is still right for you. Do not rely solely on the benchmark printed in your annual statement. Ask what funds you are invested in, how much risk you are taking and what you are paying for them.

Pensions are one of the few areas of personal finance where decisions made in the background can determine whether retirement feels comfortable or precarious.

Ignoring them may feel harmless.

It rarely is.

Antonia Medlicott is the founder of the personal finance site Investing Insiders