Chrome gained most of the share that IE lost, a trend in place since late 2009 when Mozilla Firefox's growth stalled. Firefox lost about one-tenth of a percentage point in September to end the month at 22.5 percent.
Firefox is in danger of losing its second-place spot to Chrome: If the two browsers keep to their pace over the last year, Chrome will overtake Firefox in June 2012. That's about six months later than projections based on data from rival metrics company StatCounter.
Chrome will crack the 20 percent mark in March 2012 if maintains its current tempo.
Apple's Safari was the only other browser besides Chrome to gain share in September. Using a boost in browsing by Mac machines, Safari exceeded 5 percent for the first time, said Net Applications.
Net Applications calculates browser usage share with data obtained from more than 160 million unique visitors who browse 40,000 Web sites that the company monitors for clients. More browser statistics can be found on the company's site.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is email@example.com.
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