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 Dealertrack Technologies (TRAK.DL), a provider of software and services for the automotive retail industry, slumped on Tuesday after the company reported its fourth-quarter earnings. After falling by as much as 10%, the stock was down around 8% by 12:15 p.m.

So what: Dealertrack beat analyst estimates for revenue and matched them for earnings, but that didn't help the stock on Tuesday. Revenue grew by 88% to $237.3 million during the fourth quarter year-over-year, and by 77% to $854.4 million for the full year, but much of this growth was driven by acquisitions. Dealertrack spent $555 million on acquisitions during 2014, financed by greatly increasing its debt load.

While non-GAAP earnings were positive during the fourth quarter, nearly doubling year-over-year, the company lost $6.4 million on a GAAP basis, compared to a $3.7 million loss during the fourth quarter of 2013. For the full year, Dealertrack's net loss was $17.3 million, down from a $5.9 million net gain during 2013.

The company has guided for revenue between $1.08 billion and $1.1 billion in 2015, representing 26%-29% growth, with a GAAP net loss of $20 million expected. Non-GAAP earnings are also expected to decline.

Now what: It's hard to say exactly why shares of Dealertrack declined, as the earnings results were about what analysts were expecting. Guidance for continued and growing GAAP losses despite growing revenue could be to blame, as could the expected decline in non-GAAP earnings in 2015.

Dealertrack has been growing steadily for the past decade, although its profitability has been erratic, especially after the financial crisis. The company has been profitable during most of the last 10 years, but the operating margin has been steadily falling since 2011, and has now turned negative. With a return to profitability nowhere in sight, it's difficult to get too excited about the company's rapid revenue growth.