A data-sharing scandal and privacy concerns appear to be taking a toll on Facebook.

Its stock dropped nearly 20 percent as of Thursday afternoon — a day after the company released earnings showing that its user growth has stalled and told investors that it expects revenue growth to slow for the rest of the year.

With a loss of more than $90 billion in its value, the social media giant is poised to have one of its worst trading days.

"The company did actually see a 31 percent rise in profits from a year ago, which would be great for a lot of companies," NPR's Laura Sydell reported. "But not Facebook, because it's been such a rocket ship of growth that that wasn't enough to keep Wall Street happy."

On Thursday, Facebook announced that its daily active users grew to 1.47 billion in the second quarter, but the company saw no user growth in the U.S. and Canada and a drop of 3 million users in Europe.

Chief Financial Officer David Wehner told analysts that the rollout of Europe's new privacy law — the General Data Protection Regulation — cut the number of users there and could hurt Facebook's revenue growth in the future.

Earlier this year, Facebook revealed that 87 million of its users had their data improperly shared with Cambridge Analytica, a data analytics firm that had worked with the Trump campaign. In April, CEO Mark Zuckerberg faced questioning before Congress about Facebook's role in the scandal.

Facebook stock was at $178.04, down 18 percent in early-afternoon trading Thursday.

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