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 YRC Worldwide (NASDAQ:YRCW) fell more than 15% early Thursday, then recovered partially to close down around 7% after the shipping company's first quarter loss widened from the same year-ago period.

So what: Quarterly operating revenue fell 4.2% year over year to $1.211 billion, which translated to an operating loss of $32.4 million, and a net loss of $3.95 per diluted share. By comparison, YRC turned in a net loss of $2.93 per share in the first quarter of 2013. Adjusted EBITDA also fell by more than 60% over the same period to $23.4 million.

Now what: CEO James Welch lamented, "This was one of the worst winter seasons in my more than 30 years in trucking. We estimate that it negatively affected our operating income by approximately $20 million. The main culprits were lower volumes, decreased productivities and higher use of purchased transportation."

He went on to insist YRC Worldwide has laid the foundation for future operational improvements thanks to policies implemented as part of the ratification of their new Memorandum of Understanding. However, he added, "I believe it will take the better part of 12 months before we experience the full effect of the operationally related policy changes."

If that's true, investors could be in for more pain in the coming quarters. For now, that's why I personally prefer to keep tabs on YRC's progress from the sidelines.

Steve Symington has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.