https://www.forbes.com/sites/taxnotes/2023/03/20/are-the-superrich-more-burdened-and-paying-the-highest-tax-rates/
As a group, the rich had 10.1 percent of total AGI and paid 20.4 percent of total federal individual income tax. Meanwhile, the superrich had 6.5 percent of total AGI and paid 12.3 percent of total federal income tax. The rich had an average AGI of $2.2 million with federal income tax equal to 27.5 percent of AGI, while the superrich had an average AGI of $31 million with an average tax rate that was 2 percentage points lower than that of the rich, that is, 25.5 percent. So even though federal income tax is progressive throughout most income levels, it turns out that it isn’t progressive at the highest level. This is illustrated in Figure 1.