Yahoo! has announced details of a new search marketing ranking model.

Set to be launched on February 5th, the service will rank all American-based search advertisements on quality as well as the bidding price companies have paid for keywords.

Tim Cadogan, vice president of search marketing, said: "By encouraging advertisers to focus on the quality of their ads, we can deliver a better search experience for all of our customers. Everybody wins."

He added that by delivering more relevant advertisements for users, the company believes it will create a "more valuable marketplace" for its clients.

Under the service, advertisers will also be able to get a forecast of clicks their marketing campaigns will receive, based on budget allocations and the quality of their advertisements.

The new platform is set to be rolled out to countries outside the United States from April.

Meanwhile, the search engine giant announced it generated revenue of $6,426 million (£3,253 million) during 2006.

In the last three months of the year, Yahoo! saw revenue from marketing services increase to $1,490 million, a rise of 13 per cent from the same period in 2005.