Jefferies has raised its year-end target for the S&P 500 index to 6,600 from the previous 5,600, reflecting optimism about the U.S. stock market's performance in 2025. This upward revision is driven by resilient corporate earnings and strong contributions from technology and artificial intelligence leaders such as Nvidia and Microsoft. As of late August 2025, approximately 98% of S&P 500 companies have reported earnings, with 80% surpassing analysts' expectations. The robust earnings season and positive economic indicators have eased concerns about the U.S. economy's health. Additionally, the S&P 500 has achieved 19 new all-time highs in 2025, underscoring the market's continued upward momentum.