Zynga (ZNGA) users are ditching the company -- and the stock is getting killed as a result.

Cowen analyst Doug Creutz said the daily activity on Zynga's social games fell 8.2% in May -- and that was after a 12% decline in April. He says the company is in a user tailspin. Take that 20% decline over two months and annualize it, and "that's a pretty severe rate of decline," he says in the following video.

Post continues below.
Zynga shares fell more than 10% Tuesday to close at $4.98 after Creutz issued his report. Just three months ago, shares were at nearly $14.

Zynga is directly tied to Facebook (FB), since it's the biggest developer of games for use on the social network. Some of Zynga's most successful games on Facebook include "FarmVille" and "CityVille." The games are free to play, but Zynga makes money when users plunk down real dollars to buy in-game items, such as farming equipment.

Both companies are hurting as users transition to mobile. Facebook has had problems getting a solid revenue stream from mobile users -- it doesn't display mobile advertising -- and Zynga has struggled to get users to transition to its mobile games. You can't blame Zynga for trying -- it spent a reported $180 million to buy the once-hot DrawSomething game, but even that game has lost daily users.

Zynga debuted last December at an IPO price of $10 a share.