The recent loss of momentum in the technology and AI space has had a big impact on the US market, where many of the largest tech companies are based. This shift has led to an alternative version of the flagship S&P 500 stock index whose movements are driven equally by each individual company – rather than being determined based on their size – start to perform better than the standard index in recent weeks.
At the time of writing, the information technology sector accounts for 33.4% of the S&P 500 index – the next biggest sector is financials which accounts for 12.9%. Nine of the top 10 constituents, with Berkshire Hathaway the exception, have direct links to the artificial intelligence theme. Even Berkshire itself invests in some of these companies.
Despite the volatility seen across the Atlantic this year, the US remains the largest and most heavily traded global equity market. It encompasses hundreds of world-leading companies, and the economy continues to enjoy much higher levels of productivity relative to other parts of the world.
So, you can see why an investor might want to get exposure to the US even if they are worried about how closely tied the fortunes of the S&P 500 are to technology and, particularly, AI.
What are equal-weighted products and how could they help?
Most stock market indices are weighted according to market valuation, which means the largest stocks have the biggest impact on movements in the index.
For example, if Nvidia, which by itself accounts for around 7.3% of the S&P 500, were to fall 17% in a day as it did in 2025, this alone would drag the index down by 1.2%, a relatively big move.
An equal-weighted S&P 500 index, as the name suggests, is constructed differently so all the constituents have the same weighting.
How much difference does equal weighting make?
The main way the difference can be seen is in the sector breakdown for the respective indices.
The charts show how this affects the sector breakdown in the index, with tech shares much less dominant in the S&P 500 Equal Weight than in the standard S&P 500.
There are several exchange-traded funds available on the UK market which track the S&P 500 Equal Weight index. The table shows the largest by assets.
Something investors must bear in mind is that these products come with higher charges than those which simply track the S&P 500 as they are more specialist.
The S&P 500 Equal Weight index has underperformed the S&P 500 on a five-year view, with that underperformance particularly evident in the last few years when tech names have dominated. However, as the table shows, this has shifted, with the equal-weighted index outperforming since early November 2025.
What about ex-US funds?
For investors who want exposure to global markets without the US, there are also fund options available which offer zero US exposure, which are typically named ‘global ex-US' funds. In many global indices, such as the MSCI World, the US alone accounts for about 75% of the index, which is more exposure than some may want. Investing in a global ex-US index allows exposure to the majority of the index, excluding that piece from the US.
For investors that still want some degree of US exposure, but not to a lesser extent, another option is investing in the US separately which allows for greater control in the allocation amount. These include companies from across the world but not those from the US and they have been growing in popularity.
Tom Sieber: Content editor
Tom Sieber is AJ Bell's Content Editor. He was previously the Editor of Shares Magazine. He has been with the business since 2012.
Tom is a regular contributor to the AJ Bell Money & Markets...
