Microsoft's Windows 7 operating system that launched in 2009 is proving extremely successful, it seems, according to the latest sales figures released by the company in its latest earnings report.

According to Microsoft the urge to ditch Vista and upgrade has meant that it has sold over 175 million copies of the OS in less than a year.

That number means that Microsoft has continued to sell seven copies every second, since its launch.

It also means that Windows 7 is now running on more than 16 per cent of all PCs worldwide.

"It's exciting to see this kind of response from customers who have helped make Windows 7 the fastest selling operating system in history", said the company.  

Not surprisingly, with huge sales figures like that, Microsoft announced record fourth-quarter revenue of $16.04 billion for the quarter.