Important points
The S&P 500 index fell 0.3% on Wednesday, October 30, as the latest GDP data showed an unexpected slowdown in economic growth in the third quarter. Supermicrocomputer stocks plunged after accounting firm EY resigned as server and data auditor. Garmin stock soared after the maker of fitness monitors and other wearable devices beat quarterly estimates and raised its full-year outlook.
Major U.S. stock indexes traded in positive territory for much of Wednesday’s session, but stalled in the afternoon and closed slightly lower.
The mid-week trading day seesawed after the latest gross domestic product (GDP) data showed economic growth unexpectedly slowing in consecutive quarters. . Although the downturn in the housing market weighed on economic performance, one bright spot was consumer spending, which recorded the highest growth rate since the first quarter of 2023.
The S&P 500 closed down 0.3% for the day. The Dow Jones Industrial Average fell 0.2%, and the Nasdaq index fell 0.6% due to poor performance in the tech sector.
Super Micro Computer (SMCI) stock plunged 32.7%, giving up nearly a third of its value and enduring the steepest single-day decline among the S&P 500 stocks. The plunge came after regulatory filings revealed that accounting giant EY had resigned as the server and data storage provider’s auditor. Supermicro’s accounting practices have been under scrutiny since short seller Hindenburg Research released a report in August accusing the company of “manipulation.” Supermicro said it disagreed with EY’s decision, but stressed that it takes seriously the concerns raised by the accounting firm.
Shares of power and high-frequency semiconductor producer Quarvo (QRVO) fell 27.3% after the company posted an unexpected loss for the second quarter of 2025. The company also warned that the weak performance could continue for the remainder of fiscal 2025. It cited an “adverse mix” related to customers choosing entry-level Android 5G smartphones at the expense of mid-range models.
Business IT solutions provider CDW Corporation’s (CDW) shares fell 11.3% on Wednesday after third-quarter sales and profits fell short of expectations. An uncertain economic environment led to restrained spending, project delays and weak hardware demand from corporate and small business customers, weighing on CDW’s results.
The S&P 500’s top performer on Wednesday was the stock of wearable device and GPS navigation provider Garmin (GRMN), which soared 23.2%. The gains came after Garmin reported better-than-expected sales and profits in the third quarter, with year-over-year sales growth across all business segments. The company also raised its full-year sales and profit outlook, expecting the momentum to continue through the important holiday season.
Shares of packaging manufacturer Smurfit Westlock (SW) rose 12.0% after the company released its first earnings report reflecting the results of the combination of Smurfit Kappa and Westlock, which completed in July. did. Although the results were below the highest and final estimates, the company highlighted that merger-related costs contributed to the quarter’s net loss. Smurfit WestRock also highlighted sales performance driven by the addition of WestRock and strong corrugated packaging volumes, suggesting it is well-positioned for further growth.
Shares of FMC Corporation (FMC), a maker of pesticides and other crop protection products, rose 10.7% after the company beat expectations for third-quarter sales and profits. Strong sales growth in North America, cost reduction initiatives and the sale of the Global Specialty Solutions (GSS) business supported FMC’s strong performance despite the challenging environment in the agriculture industry.
