Microsoft chief executive Steve Ballmer has started the clock ticking on his retirement from his position as head of the world's largest software maker.

Speaking at an event Tuesday in Washington, D.C., Ballmer said he would preside over Microsoft "for another nine or 10 years ... until my last kid goes away to college."

Ballmer, 52, is married with three children.

If he follows through on his plan, Ballmer would retire at about the age of 62 -- a not uncommon timeframe for top software executives who've made billions of dollars over the life of their careers.

Microsoft chairman Bill Gates earlier this week made his last major speech to the company's customers and developers before fading into semiretirement and a life of public philanthropy at the age of 52.

Some pundits have called on Ballmer to immediately resign as Microsoft's CEO in the wake of the poor reception received by the company's Windows Vista operating system and its bungled negotiations to buy out Internet rival Yahoo.

There is no clear succession plan in place at Microsoft. Chief software architect Ray Ozzie has been touted by some as a possible successor to Ballmer, however he and Ballmer are roughly the same age.

Microsoft is currently undergoing a changing of the guard that extends beyond Gates' departure.

Earlier this year, Joanne Bradford, who was chief media officer for the company's MSN Media Network, resigned to join advertising startup Spot Runner. Bradford also previously served as Microsoft's VP for sales and marketing and as chief media revenue officer.

In January, Microsoft confirmed that Rob Short, corporate VP for Windows Core Technology, had quit. Short, a 19-year Microsoft veteran, led the team responsible for designing, developing, and testing Vista.

In addition, Microsoft Business Division president Jeff Raikes has said he would retire in September, to be replaced by former Juniper Networks chief operating officer Stephen Elop.

Microsoft's mergers and acquisitions chief Bruce Jaffe stepped down at the end of February.

All of that leaves Ballmer, for now at least, as the man clearly in charge at Microsoft. On Tuesday, his famous ebullience was on display. Speaking to a group of top federal technology leaders and lawmakers, including U.S. Reps. Christopher Shays, R-Conn., and Nydia Velazquez, D-N.Y., at a dinner hosted by the American Electronics Association, Ballmer made light of a recent incident in which he was egged by a protester.

"People only videotape when something weird happens," Ballmer joked, referring to the fact that the episode has become a viral hit on YouTube.