In the gaming industry, trends move fast. That's a lesson Zynga, the social gaming company behind FarmVille, learned the hard way: Founded in 2007, it experienced a meteoric rise. But as users began to ditch Facebook for mobile games like Angry Birds, the San-Francisco-based company was slow to adapt. Stocks plummeted and hundreds of employees were let go. Now the maker of Angry Birds is also feeling pressure to stay current in a rapidly evolving industry. Rovio Entertainment, the Finnish gaming company responsible for the once red-hot franchise, announced its full-year financial results today, and they're not encouraging. After years of rapid growth, Rovio's revenue was up slightly to $216 million. Its net profit, however, plummeted: at $37 million, earnings were less than half of what they were back in 2012. Related: Zynga Makes Its Biggest Buy Yet, Announces Fresh Round of Layoffs "After three years of very strong growth, 2013 was a foundation-building year," Rovio CFO Herkko Soininen said in a statement.