Semiconductor and storage stocks lead S&P 500 gains in 2026 amid AI-driven market shifts

In 2026, the S&P 500 index is up nearly 8%, but performance varies widely among stocks and sectors. Semiconductor companies like Intel and storage firms such as Seagate and SanDisk have seen significant gains due to AI-related demand, with Intel rising over 209% and SanDisk surging nearly 499% year-to-date. Meanwhile, major tech giants like Microsoft remain in the red, and some sectors like medical devices and advertising are down. These trends highlight how AI and data storage needs are reshaping market leadership in 2026.