"If you look at the infection rate on Windows systems you can see older versions are infected more than newer machines. Windows XP is six-times more likely to be infected than Windows 8, even though it has the same malware encounter rate," said Mike Reavey, GM of Microsoft Trustworthy Computing, at the RSA Conference in Amsterdam.
He added: "The downward rate is a sign of secure development practices," he said. "In pretty much every service in Microsoft we have people devoted purely on security, focused on what's going on in the marketplace and what's needed to secure it.""
Link to Original Source