Why Qualys Inc Stock Tumbled Today

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 Qualys Inc were down 28.5% as of 11:30 a.m. Tuesday after the cloud security and compliance solutions specialist announced mixed first-quarter results and lowered its full-year guidance.

So what:Quarterly revenue grew 24% year over year to $37.4 million, which translated to adjusted net income that more than tripled to $5.5 million, or $0.15 per diluted share. Analysts, on average, were only expecting adjusted earnings of $0.11 per share, but on slightly higher sales of $38 million.

In addition, for the current quarter Qualys expects revenue of $39.5 million to $40 million, with adjusted net income per diluted share of $0.09 to $0.11. The midpoints of both ranges were below Wall Street's models, which called for revenue and adjusted earnings of $40.7 million and $0.13 per share, respectively.

Finally, for the full year, Qualys sees revenue of $165 million to $166.5 million, or a decrease from its previous guidance range of $167.3 million to $169.3 million. At the same time, Qualys reiterated its expectations for adjusted net income per diluted share of $0.50 to $0.55. Analysts, for their part, were calling for 2015 revenue and adjusted earnings of $168.4 million and $0.53 per share, respectively.

Now what:"While our growth rate for our other products remains unchanged," explained Qualys CFODon McCauley, "we project a lower growth rate for our Vulnerability Management business than we did at the beginning of 2015."

To Qualys' credit, McCauley also noted the earnings guidance remained unchanged, as the company should be able to "effectively manage costs and leverage the strength of our platform."

Even so with shares of Qualys already trading for a lofty 57 times next year's expected earnings, it's relatively unsurprising the market is taking a step back given today's miss. For now, that's why I'm perfectly content watching Qualys from the sidelines.

The article Why Qualys Inc Stock Tumbled Today originally appeared on Fool.com.

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