Americans conducted 10.8 billion core searches* in May 2008, with Google and Yahoo increasing market share slightly, according to a monthly comScore qSearch analysis of the US search marketplace, MarketingCharts reports.

Core Search

In May, Google Sites' share of core searches reached 61.8 percent, up from 61.6 percent the previous month. Yahoo Sites ranked second with a 20.6 percent share (up from 20.4 percent the prior month), followed by Microsoft Sites (8.5 percent), AOL LLC (4.5 percent) and Ask Network (4.5 percent).

Americans conducted 10.8 billion searches at the core search engines — a 2 percent increase from April:

Google Sites handled nearly 6.7 billion core searches, followed by Yahoo Sites with 2.2 billion, and Microsoft Sites with 920 million.

Expanded Search

In comScore's May 2008 analysis of the Top 50 properties where search activity is observed, Google Sites led with 8.8 billion searches.

Yahoo Sites ranked second with 2.4 billion searches, followed by Microsoft Sites (963 million), and AOL LLC (831 million).

*Based on the five major search engines, including partner searches and cross-channel searches. Searches for mapping, local directory, and user-generated video sites that are not on the core domain of the five search engines are not included in the core search numbers.