Does marginal tax and average tax rates increase when taxable income increases?

Yes, marginal tax rates typically increase as taxable income rises, especially in progressive tax systems where higher income brackets are taxed at higher rates. This means that the additional income earned is taxed at a higher rate than lower income levels. However, the average tax rate, which is the total tax paid divided by total income, may not necessarily increase at the same rate, as it reflects the overall tax burden across all income levels. Consequently, while marginal rates increase with income, average rates can fluctuate based on deductions, credits, and the overall distribution of taxable income.