The market in 2025 certainly kept us on our toes, didn't it? We saw the S&P 500 push forward with a solid return of over 17% year-to-date, marking the fourth year of a bull run. But "smooth sailing"? Not exactly. Early in the year, tariff uncertainties sent the major indexes into a bit of a tailspin, making many of us wonder if we were heading for a bear market.
Then, something remarkable happened. As the dust settled on the tariff situation and inflation showed a downward trend, coupled with better-than-expected corporate earnings, stocks staged a dramatic V-shaped rally. It was a move we haven't seen with such intensity in decades, reminiscent of the rebound after the COVID-19 pandemic in 2020. This kind of price action often sets the stage for continued market strength, though as we all know, markets are inherently unpredictable.
What's fascinating is how certain themes can really drive pockets of the market. Artificial intelligence, for instance, was a major catalyst, propelling sectors like information technology and communication services to the forefront. Interestingly, though, this AI-driven surge seemed to lose some steam towards the end of the year, with tech companies lagging in December.
Speaking of the end of the year, the "Santa Claus Rally" – that statistically strong period from the last few trading days of the year into the new year – didn't quite deliver its usual festive cheer in 2025. Historically, a negative Santa Claus Rally can sometimes signal a tougher period ahead, perhaps flat markets or even opportunities to buy at lower prices, as we saw in April. Of course, it's not a hard and fast rule, and 2025 itself proved that.
While the headlines often focus on the biggest winners, it's worth remembering that even during strong bull markets, the gains aren't always concentrated. The top three performers in the S&P 500 in 2025, for example, represented a surprisingly small fraction of the index's overall weight. This suggests that while some companies might grab the spotlight, a broader market participation can still be at play.
Looking at those standout performers, Sandisk (now part of Western Digital) made quite a splash. Spun off and relisted in early 2025, it saw an incredible surge, rising over 560% from its debut. Its strength was fueled by robust demand for its data storage solutions, particularly solid-state drives, and its advanced BiCS8 QLC technology finding traction in AI edge devices. The outlook for fiscal 2026 also looked promising, with strong EPS growth expected. Western Digital itself, as the parent company, also saw significant movement, though Sandisk's performance was particularly noteworthy.
It's these kinds of stories – the V-shaped recoveries, the thematic drivers like AI, and the individual company triumphs – that paint a richer picture of the market than just a list of the "most volatile" stocks. Volatility, after all, is often just the flip side of opportunity, and understanding the forces behind it is key to navigating the ever-changing investment landscape.
