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 trucking company YRC Worldwide Inc. (NASDAQ:YRCW) jumped as much as 13% in early trading today after the company announced earnings. Shares settled to about a 4% gain midday.

So what: Fourth-quarter revenue for YRC was up slightly to $1.22 billion, with net income of $6.4 million, or $0.16 per share. The results easily topped Wall Street's expectation of a $0.26-per-share loss in the quarter.  

Now what: The improved results were driven by increased utilization during the quarter, not falling fuel prices. In fact, management said that falling fuel prices would be a headwind because fuel surcharges will be down as long as energy prices stay low. It's certainly a positive that YRC Worldwide could swing to a profit in the fourth quarter, but given the $185.5 million comprehensive loss for the year and the fact that margins are still extremely low, there's just too much risk in this shipping business for me to be a buyer today.