Web analytics firm Compete, which based its report on data from a diverse sample of more than two million U.S. Internet users, said the volume at Microsoft's fledgling search engine continued to grow in September. "Bing saw another month of 0.3 percentage point search share growth, which has the Microsoft engine sitting pretty during an otherwise tepid month for search engines," said Compete's Marko Madjarac on Thursday.

Earlier this month, however, Dublin-based StatCounter reported that Bing's U.S. search share fell from 9.64 percent in August to 8.51 percent in September -- even as Yahoo's share fell from 10.5 percent to 9.4 percent.

"The trend has been downward for Bing since mid-August," said StatCounter CEO Aodhan Cullen, based on an analysis of 1.1 billion search-engine referring clicks. "The wheels haven't fallen off, but the underlying trend must be a little worrying for Microsoft."

A Long Way To Go

With the return of students to U.S. schools last month, online users submitted 200 million less queries than in August. Yahoo accounted for half the shortfall by serving up 100 million less queries for an eight percent decline, Madjarac said.

"In contrast, Bing's web search served 25 million more queries than (in August), continuing the engine's impressive growth since its launch at the beginning of June," Madjarac said.

Bing users last month averaged about five searches per user, per day, whereas Google users averaged about 5.6 searches and Yahoo users 7.8 searches, Madjarac explained. "So the bottom line is that Bing growth is even more impressive," he said.

Still, Bing has a long way to go if it is to mount a serious challenge to Google, which has maintained a level of nine billion queries served per month for most of this year, according to Boston-based Compete. Moreover, as Google's latest financial report indicates, the search giant "continues to capture solid sponsored search clicks, with six percent of all clicks on search results being on a sponsored link," Madjarac said.

The Bigger Picture

Microsoft had high hopes for gaining search-market traction at Google's expense when it announced a search partnership with Yahoo earlier this year. However, Yahoo racked up a search loss of one percentage point in September in comparison with August, and a loss of five percentage points since the same time last year, according to Compete.

Google served fewer queries in the month as well, "but because of the drop in overall volume across the engines, Google's search share stayed stable at close to 73 percent," Madjarac explained.

Looking at the bigger picture, StatCounter reported that Bing's search share declined on a global basis from 3.58 percent to 3.25 percent in September. Moreover, the same global trend was mirrored at Microsoft's new search partner, the Web analytics firm said.

Yahoo saw its search share fall to 4.37 percent from 4.84 percent, said the Dublin-based firm, which bases its worldwide analyses on 4.6 billion search-engine clicks. By contrast, Google boosted its status as the global search leader by increasing its share by more than two percentage points in September to 80.08 percent, StatCounter added.