Shares in the maker of Angry Birds have lost half their value since they listed on the stock market last October.

The latest plunge came Thursday after the company -- Rovio -- warned its revenues are likely to take a hit this year. Its shares fell by 46% on Finland's main stock exchange in Helsinki.

Rovio failed to take off after the IPO, which valued the company at about $1.1 billion. After Thursday's share price collapse, the Finnish gaming company is now worth just $500 million.

The company said it expects revenues of between €260 million ($319 million) and €300 million ($369 million) in 2018, compared to €297 million ($365 million) in 2017. Rovio said profits could also be lower than last year.

Angry Birds has been downloaded over 3.7 billion times. But investors have long been worried about Rovio's ability to churn out new hit games and absorb the high cost of getting new users.

"While Rovio's games revenues have improved in recent quarters its lower than expected profits forecast highlight the increasing competition in the mobile games industry," said Jack Kent, director of mobile media at ‎IHS Markit.

The company got a big boost from "The Angry Birds Movie" in 2016, which grossed nearly $350 million in ticket sales worldwide, according to Box Office Mojo. A sequel is planned for 2019.

However, Kent pointed out that the share of revenues from Rovio's licensing business is falling.

Related: Angry Birds, angry investors

There are plenty of examples of "one-hit wonders" in the gaming world.

King Digital Entertainment, the company behind Candy Crush, was bought by Activision (ATVI) for $18 a share -- 20% bellow its IPO price.

And the 2011 IPO of Zynga (ZNGA), the maker of Words with Friends and FarmVille, also turned out to be a disappointment. Its shares have fallen from $10 to roughly $3.60.