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What: Shares of Iridium Communications (NASDAQ:IRDM) have plunged today by as much as 19% after the company reported earnings that fell short of expectations.

So what: Revenue in the second quarter added up to $94.7 million, a bit light compared to the consensus estimate of $99.3 million. Net income was $15.4 million, or $0.18 per share, which also looked soft next to the $0.22 per share profit that the Street was modeling for. Declining revenue and higher projected warranty costs adversely affected results.

Now what: CEO Matt Desch said the company continues to see short-term challenges in parts of the business, and as a result Iridium is reducing its long-term outlook for the year. Full-year billable subscriber growth is now expected in the range of 10% to 15%, down from the prior forecast of 15% to 20% growth. Operational EBITDA should be $210 million, down from the previous guidance of $215 million to $225 million.

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