Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of laser and optics manufacturer II-VI (NASDAQ:IIVI) dipped as much as 10% after reporting second-quarter results that widely missed Wall Street's expectations.

So what: For the quarter, II-VI reported a 1% decline in revenue to $125.9 million, as domestic revenue gains of 3% were offset by international slowness, which caused a 3% decline in revenue. Net income for the quarter fell 8% to $0.19. Wall Street had been expecting II-VI to report a profit of $0.21 on revenue of $138.1 million. Furthermore, II-VI's third-quarter forecast, while perfectly within analysts' EPS range, fell short of the expected revenue forecast by $6 million to $11 million.

Now what: The key point here is that II-VI gets about 60% of its sales overseas, and the market for optical products overseas appears worse than within the United States. What small gains will be netted domestically from a boost in telecom spending will be more than cancelled out by weakness overseas. This marks the fourth straight quarter that II-VI has fallen short of estimates and is more than enough reason to avoid the company for the time being.

Craving more input? Start by adding II-VI to your free and personalized Watchlist so you can keep up on the latest news with the company.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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