NEW YORK (CNN/Money) - Yahoo! says its users can search through more than twice as many Web pages as Google users can, sparking a battle for bragging rights between the two rivals, a newspaper report said Monday.

Yahoo! (down $0.34 to $34.60, Research) said last week that its users can search 19 billion Web pages, versus Google's (up $5.67 to $289.72, Research) stated 8.2 billion, a claim Google has challenged, according to the Wall Street Journal.

The Journal quoted a statement from Google saying, "As of now, we have not been able to verify a substantial increase to Yahoo's Web index via their search results."

When Yahoo disclosed on a corporate Web log that its search service spanned more than 19.2 billion web pages, 1.6 billion images and more than 50 million audio and video files.

Researchers at the National Center for Supercomputing Applications at the University of Illinois have called Yahoo's latest claim "suspicious," but Yahoo stands by its number, the newspaper said.

Some experts add that size doesn't matter, since the number of pages available for searching, known as a search index, isn't a significant factor for most searches, the report said.

And Yahoo was quick to play down the importance of last week's claim.

"We've always said that size is only one dimension of the quality of a search engine," the paper quoted Yahoo, the longtime No. 2 to Google in terms of the number of consumer searches it handles, as saying.

More important than the number of pages available for searching are the formulas that rival services use to display the most relevant results for a given query, said the Journal. But in the hugely competitive search industry, any claim of superiority is taken seriously.

According to the New York Times, Google held 59.5 percent of the overall search market in the four weeks ending August 6, followed by Yahoo with 28.5 percent of the market.

But in terms of local search, Yahoo had four times as many visitors as Google did in July, the Times said.

Google may soon catch up, according to Times statistics that show Google's local search share grew by 61 percent from February through July, while Yahoo's increased by 14 percent.

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