The working paper by the National Bureau of Economic Research concludes that lowering personal tax rates in most cases appears to discourage entrepreneurial activity. The study finds that a reduction of 5 percent in the corporate tax rate correlates with a doubling of entrepreneurial activity. On the other hand, if personal income tax rates were reduced across the board by 5 percent, a 30 percent decrease in entrepreneurial activity follows.
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Available for purchase at: http://papers.nber.org/papers/W9015