Congress has invented a new extreme sport: Skating on the edge of a $7 trillion fiscal cliff.

That’s the magnitude of tax increases and spending cuts that will start to hit the economy on Jan. 1, 2013, unless Congress acts.

And how Congress navigates that fiscal cliff will affect economic growth, Americans’ wallets and the country’s fiscal outlook. (Fiscal cliff: What should Congress do?)

"There is about $7 trillion there that … could be taken out of the economy in a really stupid way that would likely push us into a recession immediately," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget.

"The problem is, that takes away any real understanding of the cost of programs (government spending). If you take away the cost, you get more voters lobbying and demanding more government services because they are not paying for them," says Will McBride, an economist at the right-leaning Tax Foundation in Washington, D.C., and one of the federal tax policy watchers who is concerned about the growing share of tax filers who do not pay federal income tax.

The Heritage Foundation, a conservative, Washington, D.C.-based think tank, initially supported the earned income tax credit as an incentive to those who earn low wages to enter and remain in the workforce. The group now describes the refundable credit more as an insidious economic force, which has transformed tax day it into a celebrated event. According to the think tank, the credit redistributes income from top earners, who shoulder most of the nation’s federal income tax burden, and expands dependency.

However, most mainstream and left-leaning economists hail the earned income and child tax credits as two of the most meaningful and substantive federal income supplements available to the working poor and to families with moderate income. And these supplements, they say, are critical to families and local economies. The left-leaning Economic Policy Institute, another Washington, D.C.-based think tank, has described the 22-year-old policy as an economic element as essential as the minimum wage. In 2010, the earned income tax credit, when factored into household income, lifted 5.2 million Americans above the poverty line, according to the most recent census data available. That figure included 3 million children. By that measure, the tax credit does more to support low-income families than food stamps or unemployment benefits.

How much of your income went to taxes this year?

There’s a decent chance Apple Inc. paid a smaller share.

That’s the contention of a report released Tuesday from the Greenlining Institute, a research and public policy non-profit based in Berkeley, Calif. The report argues that Apple, which reported profit of $13 billion in its latest quarter, paid just 9.8 percent of its 2011 income in taxes. Apple, the world’s most valuable company, is one of many blue-chip tech companies whose 2011 federal income taxes checked in at something well below the marginal 35 percent corporate rate.

"The problem is, that takes away any real understanding of the cost of programs (government spending). If you take away the cost, you get more voters lobbying and demanding more government services because they are not paying for them," says Will McBride, an economist at the right-leaning Tax Foundation in Washington, D.C., and one of the federal tax policy watchers who is concerned about the growing share of tax filers who do not pay federal income tax.

The Heritage Foundation, a conservative, Washington, D.C.-based think tank, initially supported the earned income tax credit as an incentive to those who earn low wages to enter and remain in the workforce. The group now describes the refundable credit more as an insidious economic force, which has transformed tax day it into a celebrated event. According to the think tank, the credit redistributes income from top earners, who shoulder most of the nation’s federal income tax burden, and expands dependency.

However, most mainstream and left-leaning economists hail the earned income and child tax credits as two of the most meaningful and substantive federal income supplements available to the working poor and to families with moderate income. And these supplements, they say, are critical to families and local economies. The left-leaning Economic Policy Institute, another Washington, D.C.-based think tank, has described the 22-year-old policy as an economic element as essential as the minimum wage. In 2010, the earned income tax credit, when factored into household income, lifted 5.2 million Americans above the poverty line, according to the most recent census data available. That figure included 3 million children. By that measure, the tax credit does more to support low-income families than food stamps or unemployment benefits.

President Obama and first lady Michelle Obama paid $162,074 in taxes on $789,674 in adjusted gross income for 2011, the White House reported — an effective tax rate of 20.5%.

The Obama also gave 22.5% of their income to 39 different charities, a little over $172,000.

Vice President Biden and wife Jill, meanwhile, paid nearly $88,000 in federal tax on adjusted gross income of $379,035. The Bidens also paid $13,843 in Delaware state income tax and $3,615 in Virginia state income tax (related to Dr. Biden’s work as a teacher).

The vice president’s effective federal tax rate is 23.2%. The Bidens gave $5,540 to charity, a little less than 2% of income.

The Obamas’ tax return can be found here.

The Bidens’ tax information is here.

Mitt Romney, the likely Republican presidential nominee, has requested an extension for filing his tax returns, aides said.

White House spokesman Jay Carney said Obama supports changes that would require wealthy Americans like himself to pay higher tax rates.

Inherited individual retirement accounts made news earlier this year when the Senate Finance Committee proposed to make heirs empty them within five years of the benefactor’s death.

The measure, which was abandoned shortly thereafter, would have upended a system that is highly advantageous to families. Under current rules, heirs get to stretch withdrawals from an inherited IRA across their own life expectancies, meaning the assets could potentially increase in value, tax-deferred, for decades.