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 21Vianet Group (NASDAQ:VNET) fell more than 11% early Friday, then settled to close down around 4%, after the Chinese Internet data center specialist reported mixed first-quarter results.

So what: Quarterly revenue rose 34.5% year over year to $94.3 million, which translated to adjusted earnings of $0.08 per diluted American depositary share. Analysts, on average, were looking for adjusted earnings of $0.10 per share on sales of $93.53 million.

For the current quarter, 21Vianet expects revenue in the range of $103.3 million to $105.9 million, which is roughly in line with expectations for sales of $104.6 million.

Finally, 21Vianet reiterated its full-year 2014 guidance for sales of RMB2.71 billion to RMB2.85 billion. Based on today's exchange rate, that translates to a range of $436.1 million to $458.6 million, the midpoint of which is roughly $6 million below analysts' expectation for 2014 sales of $453.6 million.

Now what: 21Vianet's top-line miss wasn't all that bad. But the stock also isn't particularly cheap, trading near 23 times next year's estimated earnings and 5.7 times trailing 12-month sales. That's why I'm still perfectly happy just keeping 21Vianet on my watchlist for now. 

Steve Symington has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.