With its sites fielding 43.1% of all U.S. searches in April, Google showed a 6.6% gain since April 2005.
Yahoo maintained its search market share at 28.8% during the same period. Since April 2005, it has seen its search share decline 2.7%.
MSN experienced a 0.3% decline since March and a 3.2% decline since April 2005.
Americans made 6.6 billion online searches in April, 4% more than in March.
Google Sites processed 2.9 billion search queries, followed by 1.9 billion at Yahoo Sites, 858 million at MSN-Microsoft, 457 million at Time Warner Network, and 384 million at Ask Jeeves/Ask Network.
A new player has gained sixth place: social networking site MySpace, which processed 43 million search queries. Though that only represents 0.6% of the U.S. search market, the site's rapidly growing user base, supposedly close to 80 million, ensures that it will be a significant player in the search market in the months to come.