Income averaging for all taxpayers was a way to effectively lower the tax rate on this year’s income by spreading it over a number of prior (lower-income) years to find an average tax rate for it. The general 4-year income averaging rule expired in 1986. Currently, income averaging can only be used by farmers and fishermen for their business income and, in some cases, for lump-sum retirement plan distributions.
Items, such as interest, state and local income and sales taxes, charitable contributions, and medical deductions, claimed on Schedule A of Form 1040. Itemized deductions are subtracted from adjusted gross income to arrive at taxable income. The amount of itemized deductions is also subject to a reduction when adjusted gross income exceeds certain limits.