Microsoft Corp. Chief Executive Officer Steve Ballmer, the world’s 44th-richest person, has seen his net worth jump $786 million after announcing his retirement from the world’s largest software maker.

The 57-year-old is the second-largest individual shareholder of Redmond, Washington-based Microsoft, after co- founder and Chairman Bill Gates, the world’s richest man. Ballmer has a net worth of $16.8 billion, according to the Bloomberg Billionaires Index. He said he plans to step down within the next 12 months after serving as CEO since 2000.

“Investors want new leadership to navigate the company in a world that doesn’t rely on the PC anymore,” said Jack Ablin, who helps oversee about $66 billion as chief investment officer of BMO Private Bank in Chicago, by phone. “In a big picture sense, he’s done a good job.”

Microsoft shares rose 7.3 percent to $34.75 at the close of trading in New York. The stock has gained 30.1 percent during the year, driving up Gates’s fortune by 15.4 percent and Ballmer’s by 21.5 percent.

Billionaire Trio

Gates, 57, co-founded Microsoft with billionaire Paul Allen, in 1975, and is still its largest individual shareholder with a 4.8 percent stake. Ballmer, who joined Microsoft in 1980, holds 4 percent. Allen, 60, who controlled as much as 28 percent of Microsoft shares, now holds 2 percent, according to the index.

The world’s richest man sees about 19 percent of his $72.4 billion fortune derived from Microsoft shares and saw his net worth rise by $1.1 billion.

Almost 70 percent of Ballmer’s fortune is derived from Microsoft shares. The rest of his fortune stems from shares of Microsoft stock and dividends.

Allen left Microsoft in 1983 before beginning his career as a media, technology and sports team investor. He has about 25 percent of his $15.4 billion fortune tied to Microsoft shares, which added $251 million.

Leadership Questions

Microsoft has lost almost half its value under Ballmer’s leadership and the shares haven’t closed above $50 since his first year on the job.

Ballmer attended Harvard University with Gates. Unlike his schoolmate, who left the Ivy League institution before graduating, he stayed and received a bachelor’s degree in applied mathematics and economics. Before joining Microsoft he worked as a marketing executive for Procter & Gamble Co., the world’s largest consumer-goods producer.

Since taking over the CEO role from Gates, Ballmer has been working to bolster Microsoft’s performance in areas like mobile computing and away from the PCs that have long been powered by Microsoft’s flagship Windows software.

Last month, he presided over the biggest reorganization of Microsoft in a decade in a bid to speed development of hardware and services as the company’s Windows business suffers from the shrinking PC market and poor demand for Windows-based mobile devices.

“This is a time of important transformation for Microsoft,” Ballmer wrote in a memo. “This is an emotional and difficult thing for me to do. I take this step in the best interests of the company I love.”

He said he plans to continue as one of the company’s largest owners and remains the company’s fifth-largest shareholder.

The Bloomberg Billionaires Index takes measure of the world’s wealthiest people based on market and economic changes and Bloomberg News reporting. Each net worth figure is updated every business day at 5:30 p.m. in New York and listed in U.S. dollars.