A harsh reality is hidden beneath the surface of the stock market’s four-year upward trend. Since the October 12, 2022 trough, unrelenting excitement around AI investments has dominated market sentiment. However, this has raised troubling questions about the sustainability of a bull market driven primarily by a select few companies, while the broader S&P 500 struggles to keep pace.
Concerns regarding excessive concentration have grown more pronounced in recent weeks. Previously, the so-called Magnificent Seven served as the primary catalyst for equity gains, but the market appears to be contracting even further. Apple, Microsoft, and Nvidia alone now represent roughly 22% of the S&P 500’s total market value — a significant increase from approximately 14% in late 2022.
Other market segments, including semiconductor stocks and memory-related equities, have also delivered impressive returns, drawing even greater attention to a small group of firms fueling the ongoing rally.
**The Deterioration of Market Breadth in the Age of AI**
Data from Ned Davis Research reveals that market breadth — defined as the proportion of advancing versus declining stocks within the S&P 500 — has reached historic lows at a time when the index is hitting record highs.
Furthermore, the research firm noted that whenever market breadth diverges significantly from overall index performance, the S&P 500 tends to peak within the following months.
A report released by Themoneytimes on Monday underscores this trend with stark clarity.
“The disparity between AI-focused companies and the rest of the market is unprecedented,” stated the financial analysis and market commentary publication on X.
“From the beginning of 2024 through today, a portfolio consisting of 42 AI-related stocks has contributed 67% of the S&P 500’s total price appreciation. To put it differently, these firms have added 22 percentage points to the index’s 33% gain during this timeframe. Meanwhile, the remaining 458 constituents of the index have only managed to contribute an additional 11 percentage points.”
Amid AI’s dominance absorbing investor attention, equities outside the AI sector are finding it increasingly difficult to maintain critical technical support levels. The analysis conducted by Themoneytimes further emphasized that approximately 84% of S&P 500 companies are currently trading at least 10% below their all-time highs, pushing the majority of index components into correction territory.
This is a striking statistic given that the overall index level remains at record highs despite ongoing geopolitical conflicts, climbing bond yields, and widespread economic uncertainty.
“The core contradiction of the current market environment has become clearer than ever,” said Mark Hackett, Chief Investment Officer at Nationwide, in a statement issued on Friday.
“While strong corporate earnings and continued AI investment continue to act as robust catalysts for growth-oriented stocks, elevated long-term interest rates, inflationary pressures tied to energy costs, and narrowing market participation reduce the margin for error.”
One perspective suggests that the market simply reflects where capital is currently flowing. Technology and AI companies continue to deliver exceptional financial results. Samsung, often cited as a prime example of the AI-driven surge in memory stocks, recently announced expectations for an operating profit of $80 billion for the third quarter.
If realized, this figure would represent the highest quarterly earnings ever recorded by any technology firm globally.
A potential remedy for the market’s declining breadth could stem from easing bond yields. As highlighted by Morgan Stanley, market breadth began deteriorating after the Federal Reserve’s hawkish stance at the Jackson Hole symposium, which served as a wake-up call for investors and caused interest rate projections to rise.
Subsequently, turbulence in fixed-income markets lifted Treasury yields to 24-year peaks, adding pressure on equity valuations.
“Should bond market volatility ease sooner rather than later, we anticipate that market breadth will align more closely with index-level performance, potentially lifting both metrics higher in the short term,” wrote Mike Wilson, Chief Investment Officer at Morgan Stanley, in a recent note dated at the end of last month.
“Looking ahead, the key challenge facing equity investors lies in determining whether this disconnect between breadth and index valuation will eventually spill over into equity volatility, which has remained surprisingly subdued throughout this recent divergence.
Our assessment indicates that this dynamic will ultimately dictate how the gap between market breadth and index performance resolves itself.”