Bill Gates weighed in on the subject of taxes at various times throughout 2019. Should he be paying more? How much makes sense? Which politician has his attention when it comes to taxing the rich?

The Microsoft co-founder and billionaire philanthropist didn’t leave the conversation behind with the changing of the calendar this week. In fact, he made it the subject of his year-end GatesNotes blog post.

“This isn’t exactly the most festive topic to cover during the holidays, but it’s one of the most important debates happening in our country right now,” Gates said as he echoed what many Democratic presidential candidates have been saying and will continue to say in the race toward the 2020 election.

Gates said that the growing wealth gap in the United States calls for a solution in which those who have more money — including he and wife Melinda Gates — should pay a higher percentage in taxes. Here’s some of what he suggested:

Raise the capital gains tax.

Raise the estate tax, close loopholes that the wealthy take advantage of.

Remove the cap on how much income is subject to Medicare taxes.

Close the carried-interest loophole that allows investment-fund managers to pay the lower capital gains rate on their income.

Tax large fortunes that have been held for a long time (say, 10 years or more).

Make state and local taxes fairer — adopt a state income tax in Washington.

Gates also shot down the argument that the rich should just be left to decide voluntarily to give more of their wealth toward taxes.

“Simply leaving it up to people to give more than the government asks for is not a scalable solution,” he wrote. “People pay taxes as an obligation of law and citizenship, not out of charity. Additional voluntary giving will never raise enough money for everything the government needs to do.”