In an interview with Bloomberg Television, billionaire Bill Gates explained how he has managed to add $16 billion to his net worth this year (bringing it to $106 billion): “The strategy that’s been used on the investments is to be over 60% in equities.”

On the Bloomberg Billionaires Index, this puts Gates only behind Jeff Bezos, the article reports, “even as his charitable donations have topped $35 billion.”

The article notes that the Gates fortune holds about $60 billion in equity assets, compared to the average family office in North America which has approximately 32% in equities in 2018 (data from Campden Wealth’s 2018 global family office report).

Although higher taxes will impact his fortune, Gates expressed in an interview his continued frustration with inequality: “I doubt, you know, the U.S. will do a wealth tax, but I wouldn’t be against it. The closest thing we have to it is the estate tax. And I’ve been a huge proponent that that should go back to the level of 55% that it was a few decades ago.” Earlier this month, the article reports, the Bill & Melinda Gates Foundation released its annual Goalkeepers report which, it explains, “called for greater investment in health care, education and technology to help reduce inequality worldwide.”

The article concludes that although Gates is confident in the U.S. and global economy, he’s not expecting his investment performance to necessarily continue: “There’s reasons to think absolute returns for the next decade will be less than they have been for the last several decades.”