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Mr. Sanders has proposed a headline top tax rate of 52 percent, applying only to incomes over $10 million
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“We do not assume taxpayers change their behavior,” said Warren Gunnels, the policy director for the senator’s campaign. 
&quot;&quot;&quot;<p>... why?<p>The top marginal rate before Reagan was ~50%, and was lowered to 28%. Given this logic, you would expect that the US net tax revenue would have declined significantly in this period, which it did not. Basically, money just shifted from capital gains and corporate taxes to individual returns. If we increase the marginal rate again, it will likely just shift back without changing anything.