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 human resources company Barrett Business Services (NASDAQ:BBSI) jumped 20% today after it released earnings.

So what: Net revenue jumped 33% to $148.0 million, and net income was up 55% to $9.0 million, or $1.21 per share. Analysts only expected $1.07 per share in earnings, so results were well ahead of expectations.

Now what: Management said that a high retention rate and strong referrals are helping grow the business, and another 30% in revenue growth is expected next quarter. That bodes well for the company long term and, with shares trading at 25 times forward earnings estimates, I think there's value left in the stock. If estimates are raised to reflect the new operating conditions, it could be another catalyst for the stock.