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 regional airline operator SkyWest (NASDAQ:SKYW) fell as much as 10% in trading today after the company released fourth-quarter earnings.

So what: Revenue rose just 1% to $813.9 million but was well ahead of the $768.5 million analysts had expected. On the bottom line, adjusted earnings per share of $0.31 easily topped Wall Street's estimate of $0.13, but that didn't really tell the full story.  

One-time costs associated with the retirement of an aircraft and a contract modification led to a GAAP net loss of $27.9 million, or $0.54 per share.

Now what: Companies like to adjust for items they consider one-time events but the market isn't giving them credit for that in this earnings report. One reason may be the rocky earnings history with big losses early in 2014 swinging to adjusted profits later in the year. But when we look at the year as a whole, the company lost $24.2 million, or $0.47 per share, which is enough to keep me from buying even today's discounted share price.