Windows 7 has sold 350 million licenses in 18 months.

That passes Windows Vista, which Ars Technica reported had 330 million users after two years.

Despite besting it’s predecessor, Network World pointed out that Windows 7 is still far behind Windows XP worldwide, despite passing it in the U.S. According to Network World, the 10-year-old operating system still has about half of the global operating system market.

In a blog post Friday, Microsoft Windows Communications Manager Brandon LeBlanc said that companies who use Windows 7 have seen an average of $140 in savings per PC per year and that analyst firms have estimated more than 90 percent of businesses are currently switching to Windows 7.

The company will stop supporting XP at the end of 2014.

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