Netflix's share price, which had more than doubled since the start of the year, tumbled Monday after the company admitted that subscriber growth is beginning to slow down. In a letter to shareholders, the company said subscriber growth between April and June had been 5.2 million—1 million below its prediction, CBS News reports. The company said it had "over-forecasted" subscriber numbers in the "strong but not stellar" quarter, reports Reuters. Shares dived nearly 14% in after-hours trading following the letter, wiping around $25 billion from the company's market valuation. (The company's top spokesman was fired last month for his "insensitive" use of a racial slur when discussing comedy.)