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 business solutions provider Insperity (NSP -1.21%) dropped as much as 10% today after the company's earnings release.

So what: Third-quarter revenue was up 5.5% from a year ago to $539.9 million, but fell short of the $546.1 million analysts expected. Net income fell 12% to $9.8 million, or $0.39 per share, $0.03 below estimates.  

To make matters worse, management lowered its full-year earnings-per-share guidance to $1.35-$1.40 from a previous range of $1.51-$1.61.

Now what: Higher than expected health care costs ate up a lot of the potential profit increase, and investors clearly expected too much growth. With shares trading at 24 times the top end of this year's estimate, I think it's just too expensive to get into Insperity right now. This thesis might change if growth picks up or the stock drops, but there are better values on the market right now.