Does idea-driven growth lower the optimal top income tax rate?
Core argument: Raising the US top marginal tax rate from 50% to 75%, applying to roughly 10% of income, could generate 2.5% of GDP in revenue before behavioral responses, but may lower long-run GDP per person by about 6% through reduced innovation.
Raising the top marginal tax rate from 50% to 75% in the US, which applies to about 10% of income, could generate 2.5% of GDP in revenue before behavioral responses. However, this increase may reduce innovation and lower GDP per person by around 6% in the long run, negatively impacting social welfare. The nonrival nature of ideas means that reducing idea production affects everyone's income, not just the inventor's. High incomes incentivize entrepreneurs to transform research insights into consumer-benefiting products, but high marginal tax rates can diminish this effort. A model incorporating innovation suggests the optimal top tax rate is significantly lower than traditional calculations, potentially even negative, as subsidizing innovation could increase overall income more than redistribution gains. This highlights the importance of considering idea-driven growth when setting top income tax rates.




