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 Core-Mark Holding (NASDAQ:CORE) dropped as much as 10.6% today after the company announced earnings.

So what: In the third quarter, revenue rose 4% to $2.31 billion and adjusted earnings per share fell from $1.14 a year ago to $1.01. Analysts expected revenue of $2.41 billion and earnings of $1.22 per share, so the results were well below expectations.  

Now what: Missing expectations is never good for a stock, and the drop in profit is very concerning for investors. Shares are now trading at about 17 times earnings, which is just too expensive for me given the operational momentum. If performance picks up in coming quarters I would revisit this stock, but for now it just isn't worth the price.

Interested in more info on Core-Mark? Add it to your watchlist by clicking here.

Fool contributor Travis Hoium has no positions in the stocks mentioned above. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings, or follow his CAPS picks at TMFFlushDrawThe Motley Fool has no positions in the stocks mentioned above. 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.