Story highlights The UN decides how much states contribute to its regular budget based on gross national income

But the UN also looks at gross national income per capita -- which is very high in the US

Still, the UN's regular budget is really only a piece of what countries end up contributing to the organization

The US hasn't seen a change in payment since 2001, when the maximum contribution cap was cut from 25% to 22%

Washington (CNN) President Donald Trump not-so-subtly jabbed world leaders Monday when he said the United Nations needs to make sure "no member state shoulders a disproportionate share of the burden."

The United States has long contributed the most to the United Nations regular budget -- but has the US been paying too much? Well, it's complicated.

On the one hand, the US is paying (a lot) more than any other country on the planet to the UN's regular budget. But it's still paying less than you might expect based on the massive US economy, which accounts for a quarter of the world's gross income.

Still, China is paying way less than you'd expect given its gross national income. But when you factor in goods that some other countries are giving to the UN, plus UN criteria that look at each nation's economy per person, the US number might not look like such a crazy share of the total pot, after all.

Here's a deeper look at how much nations around the globe are footing the bill for the United Nations -- and you can judge for yourself.

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