Investors love to know what other investors are buying. I know this because the data we publish on the best-selling funds regularly ranks among the most popular pages on our website.

You’ll also see a lot of information from investment platforms this week talking about the best sellers from this year.

It’s understandable. We all like to have a point of reference for our own decision-making. And we feel safer in the pack, among the wisdom of crowds.

But are crowd-driven decisions wise?

Because Fidelity’s Personal Investing platform has been allowing DIY investors to buy a broad array of funds for decades, I have helpful data I can dip into. I extracted the lists of best sellers from 2010, 2015 and 2020.

Here's what I found out. 

Best-selling funds of 2010

Let’s start 15 years ago. How can we forget the banking crisis of 2008 that turned into a broader financial crisis causing a fall in so many different asset prices. 

But by 2010 investment confidence was returning. Yes, deep concerns about government borrowing in Europe remained - remember the PIIGS of Portugal, Italy, Ireland, Greece and Spain? 

However, stock markets often behave counter-intuitively. And so it was: the market hit a low in early 2009 and then surged.

Those with very good memories will recall some notable winners of the era. Netflix shares shone with a 224 per cent gain in 2010 after its old-world rival Blockbuster filed for bankruptcy protection. 

Some of us still have an odd hankering for the Sunday night ritual of picking a DVD from a shop shelf. 

Winners from the FTSE 100 that year were largely linked to the commodities boom - miners such as Fresnillo or mining engineering company Weir Group.

It was a good year for most stock markets, as our table below shows. 

However, many investors may have wasted a good crisis. Our data shows the best-selling fund, and by a country mile, was a cash fund. 

It is, perhaps, understandable given what had come before: investors had endured a traumatic 31 per cent fall in the FTSE 100 in 2008. 

2010 best-selling funds

1. Fidelity Cash

2. Fidelity Index UK Fund

3. Fidelity MoneyBuilder Income Fund

4. Fidelity Special Situations Fund

5. Fidelity Asia Fund

6. Fidelity India Focus Fund

7. ASI Emerging Markets Equity Fund

8. Sterling Currency Fund

9. JP Morgan Natural Resources

10. Fidelity China Focus Fund

Source: Fidelity; net fund sales top 10 for 2010 

Investors may have had specific reasons to move to cash-like investment funds - perhaps to keep money on the sidelines in readiness for investing. 

Many were likely retirees and pre-retirees, holding a chunk of their portfolios in cash to draw an income or avoid a last-minute asset price drop. This will account for much of the popularity.

As you will likely know, the evidence is clear from the long-term data: stock market investments tend to outperform cash savings; and that cash very often loses value in real terms, as it is gnawed away by inflation.

The cash fund buyers of 2010 who stuck with their choice would have paid the price in the years that followed. 

The gap between the orange inflation line and the blue of the UK bank rate below illustrates this point. 

Also of note from 2010 was a commodities fund - from JP Morgan - making the top 10. 

An unprecedented surge in commodity prices in the Noughties, heralded as a ‘super cycle’, was clearly lingering. 

But the story was also about gold, with BlackRock Gold & General Trust sat just outside the top 10 - in 13th position. 

The financial crisis had spiked demand for what is often perceived as a safer asset during times of turmoil. 

Some ‘gold bugs’ may also have been hedging against the prospect of inflation. 

But when inflation fears were replaced by an on-off deflation threat from 2012 onwards, the gold price languished.

Asia and China funds were also popular following a powerful rebound in emerging markets. 

A 59 per cent gain in 2009 and 23 per cent in 2010, in sterling terms - had clearly tempted investors into the likes of Asia and China funds. 

This trend also highlighted the risk of chasing yesterday’s winners: emerging markets tumbled in 2011.

Best-selling funds in 2015 

By 2015, the UK was adapting to the post-crisis age of austerity. 

The UK bank rate was at just 0.5 per cent. Five years on, cash had somehow retained its allure despite losing money in each year in real terms.

This was also the era of Neil Woodford. Investors were piling into his new Woodford Equity Income funds following years of strong performance running the Invesco Perpetual Income and High Income funds. 

One of these made the top 10 list in 2015 even though Woodford had left Invesco in 2013, underlining the allure of past performance. 

Of course, none of this ended well. Woodford Equity Income Fund collapsed in 2019 after investors tried to withdraw money faster than the fund could pay out due to its private company investments. 

For our part, the Woodford fund never made the grade for our Select 50 list of favoured funds.

On a more positive note, the Fidelity Special Situations fund remained popular, as it had been in 2010. 

This story does end well for those who held until today. The fund has delivered annualised growth of 9 per cent since 2010 and 8 per cent since 2015. 

Under the stewardship of Alex Wright since 2014, the fund would have turned £10,000 into £28,380. 

Best-selling funds in 2015 

1. CF Woodford Equity Income Fund

2. Fidelity Cash

3. Fidelity Index UK Fund

4. Fidelity MoneyBuilder Income Fund

5. Fidelity MoneyBuilder Dividend Fund

6. AXA Framlington Biotech Fund

7. Fidelity Special Situations Fund

8. Invesco Perpetual High Income Fund

9. Fidelity Index US Fund

10. Fidelity MoneyBuilder Balanced Fund

Source: Fidelity. Net fund sales top 10 for 2015

What happened from 2020 on...

It’s also worth noting the start of a trend - the growing popularity of global and US trackers over the UK. 

The Fidelity Index UK fell from 2nd in 2010 to 3rd in 2015 and then to 6th in 2020. 

Fidelity Index US and global trackers start to make appearances in the table, with Fidelity Index World at number 9. 

Today, after years of strong performance, they often top the best sellers’ lists. 

It’s not the only choice that has worked well for investors. The Rathbone Global Opportunities fund has been a heavy backer of AI chip maker Nvidia and thrived over the period.

Fundsmith Equity, in contrast, has had a trickier time. It backs so-called ‘quality’ stocks - those with high returns on capital employed, generous dividends and persistent earnings growth. 

In other words, companies in rude health. Such stocks flourished in the 2010s but have been forsaken for the future promise offered by growth stocks, particularly in the tech sphere, in the 2020s.

Best-selling funds 2020 

1. Fundsmith Equity

2. Fidelity Cash

3. Rathbone Global Opportunities

4. Baillie Gifford American

5. Fidelity Global Technology

6. Fidelity Index UK

7. Fidelity Global Special Situations

8. Fidelity Global Dividend

9. Fidelity Index World

10. Fidelity Index US

Source: Fidelity; net fund sales top 10 for 2020    

The surprise favourite for investors? Cash

My final observation takes us back to where we started: cash. Its appeal has endured across every period, and it remains so today. 

In recent years, deposit rates have temporarily climbed above inflation, as that same chart shows. 

However, the total returns from global stock markets - which have delivered average growth of 11 per cent a year for the past 15 years - dwarf returns from cash.

Perhaps that misses the point. Cash remains perpetually popular because it has a perpetual role in portfolios: to shelter money when markets look rocky or because the money is for a particular near-term purpose, such as forming a property deposit.

Cash funds, in particular, offer a nimble way to shelter money and then move it back into stock market investments when the time feels right. 

In the meantime, the returns are comparable with the best cash Isa rates. 

The Fidelity Cash fund shows a distribution yield just shy of 4.5 per cent. The Legal & General Cash Trust, on our Select 50 list, estimates it at 4.3 per cent. These are not guaranteed and would fall if the UK bank rate continues to fall.

Right now, the role of cash funds is getting some regulatory attention. Following the Budget decision to restrict cash in an Isa to £12,000 for under-65s from April 2027, HMRC has proposed tests to identify and restrict ‘cash-like’ investments - potentially cash funds - in stocks and shares Isas.

It would seem right for the decision-makers to consider that committed investors have, since at least 2010, been using cash funds as an important part of creating a sensible investment portfolio. And they still do today. 

Best selling funds of 2025

1. Fidelity Cash Fund

2. Royal London Short Term Money Market Fund

3. Fidelity Index World Fund

4. Artemis Global Income Fund

5. Legal & General Cash Trust

6. Fidelity Global Dividend Fund

7. Artemis SmartGARP European Equity Fund

8. Legal & General Global Equity Index Fund

9. Vanguard FTSE Global All Cap Index Fund

10. HSBC FTSE All World Index Fund

Source: Fidelity International, 2025 data as at 01.01.25-09.12.25, net sales