The alternative minimum tax was originally enacted to ensure that high-income taxpayers pay at least a minimum amount of tax if they benefit from certain deductions and other tax preference items.The AMT tax computation is a parallel system to the regular tax system with its own definitions of income and expenses, rules for income recognition and timing, exemptions, and tax rates. Although every taxpayer is subject to AMT rules, the additional tax is paid only if the tax computation under AMT rules is higher than the tax computed under regular rules.Even though the AMT was originally targeted toward high-income taxpayers, factors, including inflation and treatment of certain tax credits, can sometimes push lower-income taxpayers into an AMT situation.