Yahoo stock slammed

Shares of Yahoo slidby12per centWednesday after it reporteddisappointingearnings.

Yahoo stock closedat $28.31 US, down $3.78 a share.

Late Tuesday, the internet giant said its first-quarter profitfell 11 per cent to $142.4 millionUS.Sales forthe three monthswereup seven per cent to $1.67 billion US, but lower thanexpectationsafter subtracting advertising commissions.

Following the report,a handful of analysts shaved their earnings estimateson Yahoo's future results.

Yahoorecently launchedits new marketing platform, called Panama in the U.S., which is intended toimprovehow ads are distributed on its site byencouraging more clicks. Panamais not expected to boost the company's profits until the second half of this year.

The company's stock has been on a roller-coaster ride. It wasup 26 per cent this year, beforeWednesday's big drop. Last year, when YahoodelayedPanama's debut, the stock got hit,erasingbillions of dollars forshareholders.

Market watchers are worried that Yahoo is losing against its chief rival, Google, which has a morelucrative advertising network that could soon include DoubleClick.Google recently announced its plan to buy the online advertising placement service.

Google is set to announce its quarterly results Thursday.