Shares closed down 11.7 percent to $23.70, off $3.14 on the day on the Nasdaq stock exchange.
Facebook said its revenue was up 32 percent to $1.18 billion but that rate was slower than in the company's recent past.
The company also said operational costs had soared -- up 300 percent to $1.93 billion compared to 2011.
After the firm's report was released, stocks went higher, the Los Angeles Times reported. But stocks began falling, reaching a low of $22.28 Friday, before rising again.
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