Top S&P 500 Risers & Fallers Last Month

The rotation out of tech that characterised July has taken a breather in August, and investors are looking for a new direction. Here's what has been moving the outliers that could be the future leaders of the index.

Top Ten S&P 500 30-Day Movers

Risers

1. Cognizant (CTSH) +38%
2. Gartner (IT) +37%
3. Zebra Technologies (ZBRA) +35%
4. Paypal (PYPL) +33%
5. Microsoft (MSFT) +29%

Fallers

1. Applovin (APP) -38%
2. Honeywell Aerospace (HONA) -34%
3. Moderna (MRNA) -34%
4. Sandisk (SNDK) -28%
5. Tesla (TSLA) -24%

S&P 500 Pauses Before Data

After scoring record highs earlier in the week, the S&P 500 was in the red on Thursday, with headlines pointing to upcoming data and geopolitical factors as the main drivers. The move is the latest in a broader trend of uneven tech-stock performance as investors seek value. Growing concerns about AI spending have weighed on certain tech names, while others have surged beyond expectations, and stocks with relatively lower valuations are gaining increasing investor interest. This pattern is visible in the top-performing stocks in the S&P 500 over the last month, with a disproportionate number of tech stocks at both the top and bottom of the performance range.

Going into the final trading day of the week, the S&P 500 is set up to keep in that holding pattern, with tech contributing more to volatility than direction. However, when counting gains from earlier in the week, tech is still up 5% from last Friday. Traders might be betting that July's underperformance was the reset stocks needed to push higher, and solid earnings this week have bolstered that perception. Whether the trend will continue through the rest of the month will likely depend on upcoming data, which will determine whether the top fallers or top risers continue to drive the benchmark index. Here's what's behind the stocks with the biggest moves over the last month and what traders are looking at for what comes next:

Low Bar Helps Risers to Leap Ahead

All five top gainers are tech-related, underscoring the sector's importance in driving the index higher. However, most of them (Cognizant, Garner and Microsoft) can attribute their leadership to strong earnings beats over relatively low expectations. Microsoft was the biggest of the firms and helped reassure investors that heavy spending on AI is beginning to translate into revenue. Its fiscal Q4 earnings showed acceleration in Azure units, and Copilot subscriptions rose to over 30 million. Gartner was another beneficiary of lowered expectations, as analysts apparently did not anticipate such demand for in-person events. The company also raised its guidance above consensus expectations. Cognizant was underperforming ahead of its earnings amid a trend where investors undervalued IT companies, expecting AI to replace SaaS. But earnings showed that demand for its services has not been negatively affected by AI, and it even raised guidance. Of course, it also helped that Cognizant is making its own inroads into agentic AI development, expanding its cloud partnership with Google.

Tripping Over a High Bar

At the other end of the spectrum, some companies posted strong earnings and even raised guidance, yet saw sharp share price declines as they failed to meet high expectations. AppLovin and SanDisk were among the notable names that investors punished despite solid earnings growth. AppLovin posted a remarkable Q2 revenue growth of 53%, but the market was expecting even better results. Investors focused on management's comments that improvements in its models were slower than anticipated and were disappointed about its guidance. Sandisk's shares were down 6% after earnings, despite beating on the top and bottom lines and posting a huge 13,000% increase in EPS year over year. Investors were apparently disappointed that the company's projected $10.3-10.8 billion in revenue for the next quarter was around the midpoint of consensus, and it was just 4.6x the sales the company had in the same period a year ago.