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 PGT (NASDAQ:PGTI) fell 15% today after reporting earnings.

So what: First quarter revenue was up 26.6% to $62.7 million, and net income was up slightly to $3.4 million, or $0.07 per share. But that fell a penny short of expectations, and that was enough to sink the stock today.  

Now what: Earnings may have been a bit lighter than expected, but long-term I don't think there's a big reason to change your investment thesis. Revenue is growing quickly and SG&A costs are falling as it does. Margin pressure in the quarter was a result of lower pricing on a big project and purchasing glass from third party vendors, but a new glass plant will be completed this year and should help margins. Long-term I think the investment thesis is still in place, and this isn't a day to sell shares after a small earnings miss.

Travis Hoium 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.