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 United Rentals, (URI -0.72%) plunged as much as 10% today after the CEO gave some cautious comments to investors.

So what: Speaking at the KeyBanc Capital Markets 2015 Industrial, Automotive and Transportation Conference CEO Michael Keeland caught traders' attention by saying that May demand  was a "little softer" than he thought it would be. With that, investors sold off the stock.  

Now what: It's amazing how much the market can overreact when executives give any sort of guidance and this is a perfect example of that. Keeland was talking about sales versus expectations for a single month this year and the company lost 10% of its value. In reality, virtually nothing about the company has changed in the last few hours except that investors are getting a lower price than they were yesterday. I don't see a reason to change your investment thesis today and if you were looking to buy shares this is a great time to do so.