Section 852(b)(1) imposes a tax on the undistributed income of a tax-exempt organization that is subject to the tax on unrelated business taxable income (UBTI). The tax rate is equal to the corporate income tax rate. Section 852(b)(3)(A) imposes an additional tax on the undistributed income of a tax-exempt organization that is invested in a controlled organization. The tax rate is equal to the highest individual income tax rate. Both taxes apply to tax years ending in or with the calendar year.