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Facebook plunged 19% Thursday — and millennial investors appear to be buying the dip.

Data from the stock-trading app Robinhood shows roughly 30,000 more users own the stock today than a week ago, and that number is quickly climbing.

Follow Facebook's stock price in real-time here.

Young investors are betting that Facebook's earnings disaster and subsequent stock landslide are presenting a buying opportunity to get the stock at an attractive valuation.

Data pulled from Robinhood — the free stock-trading app popular with young adults — shows roughly 27,000 more users had snapped up the stock Thursday morning compared to the same time a week ago.

The spike in popularity also takes Facebook up to the fifth most popular stock on the brokerage, its Top 100 page shows. The social-media giant was as low as number 10, when Business Insider first began tracking the data in June.

Shares of Facebook declined as much as 26% — wiping out over $115 billion in market value — following the social network's earnings report that showed a shortfall on revenue compared to what analysts had expected and a decline in user metrics for the first time.

But while the slump may be a good buying opportunity, it didn't take Facebook into the red for the year. Wednesday's drop has shares trading at levels seen just before a data-privacy scandal surrounding the firm Cambridge Analytica and its role in Russian interference in the 2016 US presidential election surfaced.

Analysis from the stock-trading forum StockTwits points to investors being bullish ahead of the results.

Eighty percent of the discussions were bullish heading into earnings, the firm said in an email to Business Insider, adding that "investors seem unphased after seeing Facebook’s ability to weather the Cambridge Analytica news." Those investors are likely having second thoughts on Thursday.

Facebook is now down 3.2% this year.

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