[See: 15 Tax Questions – Answered.] In general, there are seven tax brackets for ordinary income – 10 percent, 12 percent, 22 percent, 24 percent, 32 percent, 35 percent and 37 percent – with the bracket determined by filers' taxable income. The federal government uses a progressive tax system, Money › Taxes Tax Structure: Tax Base, Tax Rate, Proportional, Regressive, and Progressive Taxation. 2020-01-12 The tax structure of an economy depends on its tax base, tax rate, and how the tax rate varies. The tax base is the amount to which a tax rate is applied. The tax rate is the percentage of the tax base that must be paid in taxes. To calculate most taxes, it is necessary to know the