Justifications
In his 1980 campaign speeches, Reagan presented his economic proposals as a return to the free enterprise principles that had been in favor before the Great Depression. At the same time he attracted a following from the supply-side economics movement, which formed in opposition to Keynesian demand-stimulus economics. This movement produced some of the strongest supporters for Reagan's policies during his term in office.
The contention of the proponents, that the tax rate cuts would more than pay for themselves, was influenced by a theoretical taxation model based on the elasticity of tax rates, known as the Laffer curve. Arthur Laffer's model predicts that excessive tax rates actually reduce potential tax revenues, by lowering the incentive to produce; the model also predicts that insufficient tax rates (rates below the optimum level for a given economy) lead directly to a reduction in tax revenues.
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