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What: Shares of solar manufacturer First Solar, Inc. (NASDAQ:FSLR) saw shares fall as much as 12.9% in trading Thursday after reporting earnings. At 2:10 p.m. EDT shares were near their low at a 12.6% loss on the day.

So what: Second quarter revenue came in at $934 million and net income was $13.4 million, or $0.13 per share. After pulling out one-time charges like the $86 million writedown of TetraSun, the company earned $0.87 per share, which easily topped the $0.58 analysts expected. 

A lot of articles today are mentioning First Solar reducing earnings guidance, but that doesn't tell the full story. Prior earnings guidance was for $4.10 to $4.50 per share, but after the TetraSun writedown and changes in how projects are accounted for when they're sold to yieldco 8point3 Energy Partners -- note that the full cash value is received even if earnings aren't recognized -- non-GAAP (generally accepted accounting principles) earnings tell a more complete picture. And on a non-GAAP basis, management actually raised expectations to $4.10 to $4.50 per share in earnings.

Now what: The bigger concern may have been management not having a terribly positive outlook for 2017. We know that 2016 will be good with projects due to be completed by the end of the year and new projects are being signed for 2018 and beyond. But 2017 could be a weak year if project demand doesn't grow quickly. This isn't a new concern, but it's often reignited after earnings.

I would expect a tough year next year, but keep in mind that First Solar is executing well in a fast-growing solar market right now. And investments it's making in next-generation Series 5 modules will pay off in 2018 and beyond. Investors just don't have that kind of long-term time frame in mind today.

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