"The Alternative Minimum Tax was developed about 20 to 25 years ago as a way to make sure that very high income people paid a certain percentage of their income in taxes, even when you took into account their deductions and exemptions," says Walden, a North Carolina Cooperative Extension economist and professor of agricultural and resource economics. "The point was that, of course, the tax code is filled with credits and deductions and exemptions, and depending on how big those are, any person - but in this case a high-income person - could get away with paying a very small amount of tax. So the Congress said, 'Look, we're going to leave those deductions and exemptions and credits in place, but we're simply going to limit them when you get to a certain (income) level and make sure that folks in certain income levels pay at least this percentage of their income in tax.'"

Walden adds, "Now one problem with that was when congress passed that law is they didn't index the income level to inflation. So what was high income 20 or 25 years ago now is medium income. And so the alternative minimum tax is increasingly being applied not to what we generally call rich people, but is being applied to middle-income people. And middle-income people are raising concerns about this. And that's why there has been a move - and really it's been a move over several years - but right now we have a specific bill in Congress to reduce or eliminate the alternative minimum tax. Of course the problem is - one problem is - that would eliminate some revenue from Congress, so Congress has to either reduce spending by that amount of lost revenue or find revenue in another way."