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 Dana Holding (NYSE:DAN) were left holding the bag today, falling as much as 16% after the company delivered a poor third-quarter earnings report.

So what: The auto-parts supplier missed on both the top and bottom lines, posting adjusted earnings of $0.47 per share versus estimates at $0.54 per share, while sales fell 2.7% to $1.67 billion, below the consensus at $1.78 billion. Management said the decline in sales was in part due to currency translation, a divestiture, and the end of a light vehicle program. It also cited "challenging demand in a number of end markets we serve around the world" in the construction mining and industries.

Now what: Adding insult to injury, Dana lowered its guidance for the year to sales of $6.7 billion and earnings per share of $1.76, below the analyst consensus of $7 billion in sales and EPS of $1.89. Cummins, one of the world's largest makers of truck engines, also cut its forecast in its report as global demand seems to have slowed, even as the general auto industry has outperformed this year. These problems for Dana are likely temporary as there seem to be no structural issues with the company. Demand in the construction and mining industries should eventually bounce back.