Beneath the Calm: Hidden Volatility in the S&P 500
The S&P 500, a key barometer of U.S. Stock market health, has presented a deceptively placid picture in early 2026. Whereas the index has remained near the zero mark, suggesting limited growth or decline, a closer look reveals significant turbulence beneath the surface. According to analysis from Bespoke Investment Group, substantial stock movements are occurring within the index, indicating a rapid reshuffling of capital between companies.
The Illusion of Stability
As of mid-February 2026, the S&P 500’s overall stability masks a period of considerable internal churn. Bespoke Investment Group’s analysis reveals that only 94 of the S&P 500 component companies have experienced price fluctuations of less than 5% year-to-date. In contrast, a substantial 117 stocks have moved by 20% or more in either direction.
This disparity highlights a “tug-of-war” between winning and losing stocks. The index’s overall performance is being shaped by a few large companies, obscuring the dynamic shifts occurring among a broader range of constituents. This effect is amplified by the capitalization-weighted calculation of the S&P 500, where larger firms exert a disproportionate influence on the index’s overall value.
AI’s Impact: Winners and Losers Emerge
The most pronounced divergence in performance is occurring within the technology sector, where over 40% of stocks have experienced moves of 20% or more this year. This is largely driven by investor sentiment surrounding artificial intelligence (AI).
Companies positioned to benefit from the AI boom, particularly those involved in data storage and infrastructure – such as Sandisk (SNDK) and Western Digital (WDC) – have seen significant gains, with their shares rising by approximately 150% and 70%, respectively, since the start of the year.
Conversely, software companies facing potential disruption from AI have experienced substantial declines. Intuit (INTU) and ServiceNow (NOW) have seen their share prices fall by roughly 40% and 30%, respectively, as investors assess the potential impact of AI on their business models.
Equal-Weighted vs. Capitalization-Weighted Performance
The difference between the standard, capitalization-weighted S&P 500 and an equal-weighted version of the index is particularly striking. While the traditional S&P 500 remains virtually unchanged year-to-date, the equal-weighted index has risen approximately 5.5%. This suggests that the majority of stocks within the index are performing well, but their gains are being overshadowed by the performance of a few dominant companies.
Historically, such a divergence is unusual. Bespoke Investment Group notes that only one other period since 1990 – 1992 – has seen a larger gap between the two index calculations.
A Shift Towards Resilience: The “HALO” Companies
Recent market trends suggest a growing investor preference for companies perceived as resilient to technological disruption. The term “HALO” – an acronym for heavy assets, low obsolescence – is being used to describe companies with substantial physical assets and stable business models.
Examples of HALO companies include McDonald’s, Exxon Mobil, and Deere. These businesses are seen as less vulnerable to the transformative effects of AI. Investors are increasingly seeking refuge in these sectors, contributing to the extreme performance variations within the S&P 500.
Uncertainty Surrounding Interest Rates
Adding to the market’s complexity is ongoing uncertainty surrounding Federal Reserve (Fed) policy. Minutes from the January Fed meeting reveal a debate among policymakers regarding the timing of future interest rate cuts. Some members advocate for a cautious approach, emphasizing the need for further evidence of declining inflation, while others have even considered the possibility of raising rates if inflation remains stubbornly high.
This uncertainty further fuels market volatility and contributes to the ongoing rotation between different sectors and asset classes.