Wednesday was a tough day on Wall Street, as a yield curve inversion made market participants anxious about whether the U.S. economy can continue to defy the poor economic conditions that most of the rest of the world has dealt with recently. Major indexes suffered big declines, continuing the volatile week that the market has seen. Some individual stocks saw much larger drops, and Myriad Genetics (NASDAQ:MYGN), Nordstrom (NYSE:JWN), and Luckin Coffee (OTC:LKNC.Y) were among the worst performers. Here's why they did so poorly.

Myriad concerns plague this genetics company

Shares of Myriad Genetics plunged 43% after the genetic diagnostics specialist reported its fiscal fourth-quarter financial results. Revenue climbed 11%, but that was a slower pace of growth than anticipated, and adjusted earnings falling from year-ago levels made shareholders nervous. Several key products, including the GeneSight genetic test for depression and the Vectra rheumatoid arthritis test, saw year-over-year declines in sales. Add to that some concerns about the U.S. Food and Drug Administration requesting changes to GeneSight, and it's easy to understand why Myriad investors are worried.

Myriad logo and slogan with 25-year celebration graphic.

Image source: Myriad Genetics.

Nordstrom keeps sinking

High-end department store chain Nordstrom saw its stock drop nearly 11% on a bad day for retailers in general. Some of the negative news came from retail peer Macy's, which reported poor results that called into question its long-term growth prospects. Nordstrom has faced many of the same difficulties, and although its strategy of emphasizing its lower-end Nordstrom Rack concept has matched up with shopper demand, it still hasn't entirely produced the results the company had hoped to see. The one thing Nordstrom has that other retailers lack is potential interest from the Nordstrom family to take the company private, and every move lower for the stock increases the chances that a buyout bid could be in the offing.

Luckin needs a caffeine boost

Finally, shares of Luckin Coffee finished lower by 17%. The Chinese coffee company posted what seemed to be impressive growth in the second quarter of 2019, with revenue jumping nearly 700% in local currency terms compared to year-ago levels. Luckin has nearly quintupled the size of its network to almost 3,000 stores, but even though the company succeeded in narrowing its operating losses, it didn't do enough to satisfy growth-hungry investors that it can reach full profitability in the near future. Unless Luckin can establish not only top-line growth but also a viable path to positive earnings, it'll be hard for the Chinese coffee company to meet the extremely high expectations of its shareholders.

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