Shares of the organic food retailer dropped as much as 7.4% Thursday before climbing back a bit. Since Wednesday, Whole Foods’ (WFM) stock has declined 6.9%, losing about $78 million in market value.

The reason has to do with falling same-store sales, which are sales at stores open at least one year. Whole Foods reported third-quarter results Wednesday, revealing a 0.2% drop, which was its first quarterly same-store-sales decline since 2009. Whole Foods has been squeezed by other major retailers as well as an overpricing scandal, explained Fortune’s Phil Wahba:

What’s more, Whole Foods is feeling pinched by Walmart’s grocery push and Amazon.com’s growing Fresh grocery delivery program. The company is also having trouble competing on price in a more competitive environment. And it will soon have to contend with a new grocery offering from Target.

The grocer was also hurt last summer by findings from a New York consumer affairs agency that it was overpricing some products. In July, executives said coverage of that probe had a negative effect on its earnings.

On top of all that, the future isn’t looking much better for Whole Foods: The company has said same-store sales were already down 2.1% this quarter.