If President Donald Trump sticks to what he has said, Americans earning between $149,400 and $307,900 are most likely to see an increase in their taxes as a result of tax reform.

Those figures come from a recent study by the Tax Policy Center, a nonpartisan group in Washington, and are based on Mr. Trump’s statements and proposals. The study concludes that nearly one-third of about 19 million households in that income range could see tax increases averaging from $3,000 to $4,000 a year.

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