Nielsen/NetRatings on Thursday reported September data for the top U.S. search providers. Google led not only in share of searches but also in year-over-year growth.

An estimated 2.8 billion search queries were conducted at Google search, accounting for 50.0 percent of all search queries conducted during September, according to NetRatings. Moreover, growth in the number of Google searches from Sept. 2005 was 24 percent - twice the rate of searches conducted at second-place Yahoo, which accounted for 23.4 percent of Sept. searches with 1.3 billion.

The two leaders were followed by MSN/Windows Live Search in third with 9.2 percent of searches, or 519 million - 12 percent less than last Sept. AOL was in fourth place with 6.3 percent search share and nearly nine percent fewer searches year over year.

With the second-highest rate of year-over-year growth was Ask.com, accounting for 2.7 percent of Sept. searches at 152 million - 19 percent more than Sept. 2005.