By Tim Molloy

Microsoft Corp. CEO Steve Ballmer announced his retirement Friday. Here is his email to employees:

I am writing to let you know that I will retire as CEO of Microsoft within the next 12 months, after a successor is chosen. There is never a perfect time for this type of transition, but now is the right time. My original thoughts on timing would have had my retirement happen in the middle of our transformation to a devices and services company focused on empowering customers in the activities they value most. We need a CEO who will be here longer term for this new direction. You can read the press release on Microsoft News Center.

I am proud of what we have achieved. We have grown from $7.5 million to nearly $78 billion since I joined Microsoft, and we have grown from employing just over 30 people to almost 100,000. I feel good about playing a role in that success and having committed 100 percent emotionally all the way. We have more than 1 billion users and earn a great profit for our shareholders.