Minimum taxes are intended to increase tax payments from taxpayers who, under the rules of the regular tax system, are believed to pay too little tax relative to a more standard measure of ther income. The U.S. federal income tax has both a personal and a corporate alternative minimum tax (AMT). The complex corporate tax is designed to increase the income tax on businesses by adjusting for a wide range of preferences awarded to corporations under the standard system. This article details the AMT calculation, revenues, and purpose.