Their central estimate is that the taxable income elasticity for this group is 0.46, which implies a revenue-maximizing tax rate on earned income of 56%.29 This in turn (accounting for NICs and indirect taxes) corresponds to an income tax rate of 40%.

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Krugman and Krueger cite that there is a negative relationship between social mobility and inequality based on intergenerational elasticity of income.

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Crowdsourcing has the potential to enable a new elasticity in the use of labor but it also has the capacity to drive income through the floor.

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