Rovio, creators of the popular Angry Birds phenomenon, have reported that the company's game sales were down slightly year-over-year. While it brings in a significant amount of revenue through other means with its Angry Birds and associated brands, because the company has had to take on so many more employees, due to the company's internal growth it made less then half as much money in 2013 as it did the year prior.

Rovio doesn't appear to be worried though, much of its money has gone back into the company to fund a new animation studio as well as its massive merchandising business. Plush Angry Birds and other branded consumer items make up almost 50% of the company's total sales.

It seems like Rovio will continue to rely on its dwindling gaming arm for the foreseeable near future, as its new animation studio's first major project isn't set to appear until sometime in 2016. While this could mean good news for gamers with a more complete focus on the gaming end of things, the company's game sales fell last year despite launching Angry Birds Star Wars 2 and other titles.

Reports suggest, Rovio's growth rate isn't really keeping pace with other major mobile publishers either. Some suggest Rovio's reliance on a very small number of IP allow companies like Candy Crush maker King (and even some smaller publisher/developers) to maintain a much steadier growth rate. The company also introduced freemium titles with in-app purchases which can tend to drive a certain segment of mobile gamers away.

Having said that, the Angry birds brand remains a strong one, with a very healthy merchandising business and having "exceeded 2 billion downloads so far, making it the most downloaded game brand ever," according to Rovio.