Understanding the S&P 500’s Concentration

Surprisingly, only a small group—just 4% of the S&P 500 companies—accounts for over half of the index’s gains. This highlights significant concentration within the market.

Many key stocks in this index are indeed on the pricey side, yet they tend to deliver quick and substantial revenue growth. This is particularly true for major players like Apple, Microsoft, Alphabet, Amazon, and Meta Platforms, which have robust financial foundations allowing them to invest in AI without much strain.

You might have come across the term “Magnificent Seven.” This refers to a set of tech giants that have reaped impressive returns lately. Included in this group are Nvidia, Microsoft, Apple, Alphabet, Amazon, Meta, and Tesla. And then there’s another group—what I like to call the “Ten Titans”—which includes Broadcom, Oracle, and Netflix. It’s intriguing to see how massive these companies are, especially when compared to others in the S&P 500.

At present, the Magnificent Seven constitutes about 35% of the S&P 500, while the Ten Titans hold about 40%. Together with the largest 20 stocks by market cap—like Berkshire Hathaway, Eli Lilly, JP Morgan Chase, Walmart, Visa, ExxonMobil, Mastercard, Johnson & Johnson, Palantir Technologies, and AbbVie—these firms represent an astounding 50.2% of this index.

This concentration has implications for investment strategies. Individual investors, as well as actively managed funds, might consider adjusting their portfolios to avoid being too heavily weighted in a few stocks.

It’s worth noting that market sentiment and earnings performance greatly influence the S&P 500’s composition. For example, NVIDIA’s market value soared from less than $500 billion a few years back to over $5 trillion recently, with its profits skyrocketing as well.

Large firms have played a disproportionate role in driving the S&P 500 upward. We can see this by comparing it to the S&P 500 Equal Weight Index, where each stock has an equal influence. In that index, stocks like Clorox don’t get overshadowed by giants like Nvidia, which currently carries about 350 times more weight.

The S&P 500 Equal Weight Index performed similarly to the main index until 2022. Since then, as tech stocks surged post-2022, the S&P diverged from its equal-weighted counterpart, leaving it behind in performance over the last several years.

This increasing concentration means investors should tread carefully, especially when it comes to index funds. Holding significant shares in some of the top S&P stocks could reduce diversification if one were to also invest in those funds, leading to a potentially greater concentration risk.

Moreover, with many of these big companies trading at elevated valuations compared to historical standards, they’re under pressure to maintain strong earnings growth. Fortunately, many can back their high valuations with solid profits and cash flow.

Companies like Nvidia, Microsoft, Apple, Amazon, and Alphabet might operate on different models, but they share a critical trait: they all have more cash and liquid assets compared to their long-term debts. It’s their cash flow that enables them to invest without relying too heavily on borrowing, which is a smart financial strategy.

This principle can extend to other major corporations as well. Take JPMorgan Chase, which boasts stability; Visa and Mastercard with their impressive margins; and ExxonMobil, known for its high-quality oil and gas portfolio, has managed to consistently grow dividends for over 40 years, even amidst excess in the industry.

For the most part, the top 20 S&P 500 stocks are climbing due to accelerating earnings. Investors are increasingly willing to pay a premium for these high-quality firms. When you invest in proven companies, it’s an entirely different ballgame than taking risks on less established or unprofitable businesses.

In summary, while this concentration in the S&P 500 might not be inherently negative, it does indicate significantly less diversification than in the past. For investors, this calls for a cautious approach when acquiring index-related products, as volatility may increase. A downturn in just a few major players can impact the entire index.

Before diving into investments linked to the S&P 500, keep some factors in mind: there are other opportunities out there worth considering beyond the typical offerings within the index.