



The above graph shows daily Firefox 3 usage rates among visitors to city-data.com as determined from Google Analytics in the two weeks since the Firefox 3.0 Download Day. City-data.com is very large website with 8.7 million unique monthly visitors (ranked 143rd largest in the U.S. by Quantcast) with 93% of them coming from the U.S. It is frequented by "mainstream" visitors. According to Quantcast, the only significant demographic variance is fewer visitors ages 17 and below than average. Higher Firefox usage during weekends is caused by higher share of home-based as opposed to work-based users. The jump caused by Mozilla's "Download Day" world record is clearly visible. Beta and Release Candidate versions of Firefox 3 were used by almost 1% of visitors even before the official version was made available.

As can be seen in this weekly graph, both Firefox and Safari have been steadily increasing their market share during the last few months in 2007 and 2008. Internet Explorer 6 continues its decline, but it is still used by a significant number of people. Most of the Firefox 3 market share gains of the last two weeks have come from existing Firefox 2 users, not yet from converts from other browsers.

This report has been created because we found that other existing reports on Firefox 3 usage do not give a representative real-world data on the U.S. browser market share (using browser share skewed by tech-oriented sites, not separating U.S. market share, not specyfing the source of data, using E-commerce sites with a lot of visitors coming from paid ads that are not seen by Adblock users, etc).