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 manufacturer Preformed Line Products (NASDAQ:PLPC) dropped 17% today, after the company released earnings.

So what: Third-quarter sales dropped 12%, to $100.8 million, and net income dropped 34%, to $6.1 million, or $1.12 per share. All four regional segments saw net income fall, so the bad news was widespread for the company. 

Now what: The weak global economy is lowering the appetite for infrastructure projects, and that's having a big impact on results. I don't see the dynamic changing quickly, and that will put pressure on earnings going forward. I'm definitely not a buyer on the drop in sales and net income today, and would wait for a pickup in end markets before jumping in.