The 2012 federal tax table contains information on tax rates applying to different filing statuses and levels of income, explains Efile.com. The Internal Revenue Service organizes the rates in distinct levels of increasing value known as tax brackets, with each level encompassing a range of incomes.
Because the U.S. tax system is progressive, the large majority of individuals pay taxes across several brackets, explains Efile.com. For this reason, the marginal rate of tax typically refers to the highest tax bracket that the last dollar of a person's income falls into and not to the general rate.
For instance, an unmarried individual who earned $40,000 in 2012 paid income taxes across three tax brackets, according to information from Efile.com. The first $8,700 attracted a 10 percent rate, while every dollar in the range between $8,701 and $35,350 drew a 15 percent tax rate. The remainder of the income, lying in the $35,351 to $85,650 bracket, attracted a 25 percent rate. In this case, the marginal tax rate is 25 percent.
The 2012 federal tax table established four filing categories, notes Efile.com. These are "married/joint," referring to married couples filing jointly; "married/separate," for married couples filing separately; "head of household" and "single." Similar incomes in different categories were subject to differing tax rates.
The information in the 2012 tax table applied to tax returns due by Apr. 15, 2013, explains Efile.com.