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 USG Corp. (NYSE: USG) are down 10% today on unusually high volume.

So what: With over an hour left in the trading day, nearly two times the average number of shares had traded hands. This high-beta stock looks to be suffering from an overall market decline and high oil prices, which may lead to lower demand in the future.

Now what: I wouldn't read into this move too much considering the overall market decline today. USG has a beta of 2.77, meaning it should (hypothetically) move 2.77 times what the market moves, and with the S&P down 2% as I am writing, the move is only slightly higher than expected. The company hasn't released any news; I don't see a reason to change the investment thesis on USG today.

Interested in more info on USG Corp.? Add it to your watchlist.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

USG is a Motley Fool Inside Value recommendation. 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.