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 U.S. Silica Holdings (SLCA 1.10%) jumped as much as 10% today after the company reported earnings.

So what: Demand for sand used in fracking jumped 45% year over year in the first quarter and helped drive a 47.2% increase in revenue to $180.1 million. Net income only increased 6.3% to $18.4 million, or $0.34 per share, which was actually a penny behind estimates.  

Now what: Management said demand for fracking sand will outstrip supply this year. That gave the company confidence to say that full-year EBITDA will be at the high end of the range of $180 million to $200 million. At 17.5 times next year's estimates, shares aren't cheap, but I think there's still room to run higher as demand picks up in U.S. Silica's end markets.