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 Rocket Fuel (NASDAQ:FUEL), a programmatic advertising company, were decimated on Friday after the company reported lackluster earnings and guided for a weaker-than-expected quarter. The stock was down more than 25% at 12:30 p.m..

So what: Revenue for Rocket Fuel's fourth quarter increased by 63% year-over-year to $139.5 million. Analysts were expecting revenue of $147.3 million. Non-GAAP net revenue, which excludes media costs, rose 54% year-over-year, while a net loss of $20.5 million was far larger than the $2.2 million net loss during the fourth quarter of 2013.

Costs rose significantly faster than revenue during the quarter, jumping nearly 80% year-over-year. The number of employees rose by 81% year-over-year, while the number of active customers only increased by 33%.

Rocket Fuel guided for non-GAAP net revenue in the range of $57 million to $58 million for the first quarter, representing growth of around 30%. If the same ratio between GAAP and non-GAAP revenue holds, this is well below analyst expectations.

Now what: After reaching a high of around $66 per share soon after its IPO in late 2013, shares of Rocket Fuel now trade around $11 per share. The hype surrounding the company was extreme when it first went public, with shares opening at twice the IPO priceĀ  and analysts attaching lofty price targets. While the company is still growing quickly, its growth has slowed dramatically, and it remains wildly unprofitable.

The hype has dissipated, and Rocket Fuel now needs to prove that it can turn a profit from its platform. With costs rising much faster than revenue, this doesn't seem likely to happen any time soon.