I’m getting an unpleasant sense of déjà vu. The top-selling investment funds of the past year are suddenly at the bottom of the performance tables and things are horribly reminiscent of 2000.

JP Morgan’s Natural Resources fund has been among the top ten best sellers every month since September on Hargreaves Lansdown’s Vantage fund supermarket. Last month it was joined by Junior Oils trust, which does what it says on the tin and invests in exploration and production minnows.

And which funds are bottom of the performance tables for July? JPM Natural Resources is second to last with a painful fall of nearly 18% in just one month, and it’s down 7% over a year. It’s closely followed by Junior Oils with a fall of 15%.

To be fair, longer-term returns still look stellar, with the JPM fund up 316% over five years, but there’s a danger investors have fallen for the marketing hype just at the top of the cycle – exactly as they did with tech.

Oil has plunged more than 20% from its peak of $147 to below $113 over the past two months alone and whereas six months ago analysts were scrambling to predict prices above $200, now the talk is of going back below $100.

More worrying for investors is the impact that the commodities sell-off has had on two of the Brics (Brazil, Russia, India and China).

Allianz RCM BRIC Stars has also been in Hargreaves Lansdown’s top ten every month since September and Neptune’s Russia and Greater Russia has featured in ten out of 11 months.

Brics have been the great hope for investors tired of the UK and scared of the US, but there are growing signs that emerging markets will singularly fail to escape the developed world’s slowdown and could in fact fare much worse.

It might surprise you that the US, home of the credit crunch, has beaten any Bric country so far this year. While the S&P500 has fallen 12%, Brazil has lost 15%, Russia and India are down 20% and China is down a whopping 54%.

Take Brazil. Fund managers would have you believe that its rise to prominence is all to do with growing domestic demand and nothing to do with an external commodity bubble – others, however, disagree.

The bulk of the upturn in Latin America’s economic performance since 2003 has come from external factors, according to investment bank Morgan Stanley. Economic growth has followed export prices (basically commodities) almost exactly, so if the latter come off the boil, Brazil’s markets and economy can be expected to follow.

Meanwhile in Russia wage growth has slowed sharply – not good for the domestic demand story; in China, economic growth is expected to tail off from 12% last year to 9% in 2009; and India is also in the midst of an economic slowdown.

You have to worry when Allianz, which launched one of the first retail funds to capitalise on the Brics concept, warns that you should review your investments, as it did last week. Its point was that you should invest in all four countries – through its fund, of course – rather than just one of them, but I would go one step further and avoid what is clearly a marketing gimmick altogether.

When the US and the rest of the world go into a slowdown, and possibly a recession, it looks increasingly likely emerging markets will follow suit.

The Brics story may not be broken long term, but I would check you haven’t been sucked in by the marketing concept and put too much of your money there.

Kathryn Cooper is editor of the Money section

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