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 mortgage insurer MGIC Investment (MTG -0.61%) climbed 15% today after its quarterly results topped Wall Street expectations.

So what: The stock has soared over the past year on a string of better-than-expected quarters, and today's surprise third-quarter profit -- $0.04 versus the consensus of a $0.10 loss -- only reinforces that trend. In fact, the percentage of loans that were delinquent, excluding bulk loans, was 9.69%, versus 12.34% in the previous quarter, giving investors plenty of good vibes over MGIC's profitability going forward. 

Now what: Don't expect the operating momentum to slow anytime soon. "I am pleased to report that the favorable economic trends we have been benefiting from relative to home price appreciation and employment over the last several quarters have continued," Chairman and CEO Curt Culver said. "I am encouraged by the progress we have made this year regarding new business writings and am pleased with the quality and performance of the business written since 2009." Of course, with the stock up a staggering 380% over the past year and trading at a price-to-book of 3.5, much of that progress might already be baked into the price.