Bill Gates Is $10 Billion Richer Than He Was In January, But Not From Microsoft

Despite his praiseworthy work as a philanthropist and a promise to give away most of his wealth, he's still getting richer all the time.

And Microsoft is not the source of most of that wealth.

Gates is worth $72 billion with Microsoft accounting for one-fifth of that, reports Forbes. Microsoft did help out in August, when Steve Ballmer announced he would resign. Shares ticked up to over $36 on that news and are still trading at over $32.

But the bulk of his money comes from other companies. His investment firm Cascade owns a big chunk of tractor maker Deere & Co., as well as Canadian National Railway and Mexican Coke bottler Femsa.

Diversifying from Microsoft was certainly smart. Gates is $9.8 billion richer since the start of 2013, according to Bloomberg's Billionaire Index. Plus, at the start of 2013, he was $7 billion richer than he was at the start of 2012.

Gates was one of the founders of something called the Giving Pledge, where wealthy people vow to give away the majority of their wealth. By some accounts, Gates has given away at least $28 billion away to charitable causes between 2007 and 2012, but clearly his wealth is still growing faster than he's giving it away.