The Dow Jones Industrial Average gained 8.6% in the first half, its strongest first-half performance since a 12.7% rise in 2021. The S&P 500 advanced more than 8% and the Nasdaq climbed 11.1% over the same period. Second-quarter returns were particularly robust, with the S&P 500 up nearly 14% and the Nasdaq up 19.6%, the largest three-month gains for both indexes since the second quarter of 2020. The Dow's 12.6% quarterly rise was its best since the final three months of 2022. Markets overcame early-year turbulence from erratic energy costs tied to the Iran conflict and doubts about the durability of AI investment, with a weekend US-Iran ceasefire agreement and reopening of the Strait of Hormuz providing a further boost on Monday.