Answer:
The U.S. government contributed just over $10 billion to the United Nations in 2018, the most recent fiscal year with full data available. About two-thirds of this total was voluntary and one-third was assessed.
The U.S. currently pays $116M each year to the World Health Organization. 24% of the entire organization's budget. China pays the second most of any country in the world at $57M, or 12% of the organization's total. The vast majority of countries pay significantly less than the U.S.
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