The U.S. stock market ended the first half of 2025 with back-to-back record highs, defying a rollicking few months of trade tensions and economic uncertainty that sent it deep into negative terrain in April.

The S&P 500, the widely followed index that underpins the retirement accounts of millions of Americans, sank into a deep correction after President Donald Trump announced sweeping tariffs, rattling financial markets in March and April. But momentum shifted over the next several weeks as the White House backed off its steepest tariffs. On Jun 30, the benchmark index closed at 6,204.95, up 0.5 percent, building on its record finish from Jun 27. It’s now up 5.5 percent for the year.

Shares of Palantir — a data integration and AI company with many government contracts — swelled more than 80 percent. Palantir recently said it would help develop software with a nuclear energy project development firm, as many countries are showing more appetite for the energy source, said Mark Giarelli, equity analyst for Morningstar. And the company separately said it would partner with Accenture Federal Services “to help federal government agencies reinvent operations with AI.”

The AI boom also extended to certain utilities and energy equipment stocks — which are expected to benefit from AI data centers’ electricity needs. NRG Energy Inc soared more than 79 percent, while the gas-powered turbine manufacturer and service provider GE Vernova jumped about 60 percent.

Seagate Technology PLC has been on an impressive run, soaring 67% over the past six months. The stock’s rally is powered by a combination of factors, including strong industry tailwinds and the company’s focus on improving profitability, reducing debt, and boosting cash flow.

The demand for mass-capacity storage is growing, driven by the growing digital shift toward cloud services and the ongoing expansion of data center infrastructure to support artificial intelligence (AI) advancements. Seagate, with its industry-leading data storage solutions, is benefiting from this surge as enterprises and hyperscale cloud providers increasingly rely on its high-capacity hard drives.

Other stocks among the S&P 500’s top 10 performers through the year’s first half include: Howmet Aerospace Inc. surging 70%, SUPER MICRO COMPUTER INC up 60%; Newmont Mining , Uber, GE Aerospace and CVS Health up 50%.