The stock market, and individual stocks, can be volatile over short periods.
A bunch of these value-shedding stocks have posted disappointing quarterly results.
Some fallen stocks can present great opportunities.
It's fun to follow stocks that soared recently, and it can be sobering to see which ones have plunged -- especially if you're a shareholder. So here's a look at the worst-performing stocks in the S&P 500 index of 500 of America's biggest companies -- in September.
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CarMax (NYSE: KMX) sells, finances, and services new and used cars at more than 250 locations. Much of its loss happened after it posted a very disappointing second-quarter report, featuring revenue down year over year and profits really down -- by 25%. This reflects lower car-buying enthusiasm from consumers.
FactSet Research Systems (NYSE: FDS) offers financial data and analytics for professional investors. It also posted results below analyst expectations.
Kenvue (NYSE: KVUE) was spun off from Johnson & Johnson in 2023 to focus on consumer products. Its brands include Listerine, Zyrtec, Motrin, Band-Aid, and... Tylenol. As you might have guessed, much of its recent downfall is tied to President Trump and others asserting that Tylenol is linked to autism.
Deckers Outdoor (NYSE: DECK) is an outdoor apparel company with brands such as Uggs, Teva, and Hoka. It has fallen in value in part due to concerns about tariff effects -- as well as general worries about economic uncertainty reining in consumers' eagerness to buy. It also disappointed investors with its last earnings report.
Synopsys (NASDAQ: SNPS) specializes in software used for designing and testing semiconductor chips. Its shares have fallen in part due to weakened demand from a major customer and export restrictions from the Trump administration (now removed).
While these stocks retreated, the S&P 500 index gained 3.5% in September. Remember, too, that when stocks plunge, you should steer clear if the company is facing lasting, intractable problems. But if the market seems to have overreacted and the company's future is promising, a much lower stock price can be a great buying opportunity.
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Selena Maranjian has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends CarMax, Deckers Outdoor, FactSet Research Systems, Kenvue, and Synopsys. The Motley Fool recommends Johnson & Johnson and recommends the following options: long January 2026 $13 calls on Kenvue. The Motley Fool has a disclosure policy.