This article is by Stephen Ohlemacher of The Associated Press.

Stung by the income taxes you had to pay this month? You'll probably take little consolation in hearing that the superrich pay a lot less in taxes than they did a couple of decades ago. And nearly half of U.S. households pay no income taxes at all.

The Internal Revenue Service tracks the tax returns with the 400 highest adjusted gross incomes each year. The average income on those returns in 2007, the latest year for IRS data, was nearly $345 million. Their average federal income tax rate was 17%, down from 26% in 1992.

Over the same period, the average federal income tax rate for all taxpayers declined to 9.3% from 9.9%.

The top income tax rate is 35%, so how can people who make so much pay so little in taxes? The nation's tax laws are packed with breaks for people at every income level. There are breaks for having children, paying a mortgage, going to college, and even for paying other taxes. Plus, the top rate on capital gains is only 15%.

There are so many breaks that 45% of U.S. households will pay no federal income tax for 2010, according to estimates by the Tax Policy Center, a Washington think tank.

"It's the fact that we are using the tax code both to collect revenue, which is its primary purpose, and to deliver these spending benefits that we run into the situation where so many people are paying no taxes," said Roberton Williams, a senior fellow at the center, which generated the estimate of people who pay no income taxes.

The sheer volume of credits, deductions and exemptions has both Democrats and Republicans calling for tax laws to be overhauled. House Republicans want to eliminate breaks to pay for lower overall rates, reducing the top tax rate from 35% to 25%. Republicans oppose raising taxes, but they argue that a more efficient tax code would increase economic activity, generating additional tax revenue.

President Barack Obama said last week he wants to do away with tax breaks to lower the rates and to reduce government borrowing. Obama's proposal would result in $1 trillion in tax increases over the next 12 years. Neither proposal included many details, putting off hard choices about which tax breaks to eliminate.

In all, the tax code is filled with a total of $1.1 trillion in credits, deductions and exemptions, an average of about $8,000 per taxpayer, according to an analysis by the National Taxpayer Advocate, an independent watchdog within the IRS.

Rep. John Tierney, D-Mass., has introduced a bill to eliminate about $60 billion in tax breaks, mostly for businesses. The bill would require a regular review of all tax breaks to see if they still serve their original purpose.

"Right how they don't even come into the conversation," Tierney said. "We need to get them into the conversation and have the information on which to make a good solid decision."

More than half of the nation's tax revenue came from the top 10% of earners in 2007.

More than 44% came from the top 5%. Still, the wealthy have access to much more lucrative tax breaks than people with lower incomes.

Obama wants the wealthy to pay so "the amount of taxes you pay isn't determined by what kind of accountant you can afford."

Eric Schoenberg says to sign him up for paying higher taxes. Schoenberg, who inherited money and has a healthy portfolio from his days as an investment banker, has joined a group of other wealthy Americans called Responsible Wealth, which is project of the group, United for a Fair Economy. Their goal: Raise taxes on rich people like themselves.

Schoenberg, who now teaches a business class at Columbia University, said his income is usually "north of half a million a year." But 2009 was a bad year for investments, so his income dropped to a little over $200,000. His federal income tax bill was a little more than $2,000.

"I simply point out to people, 'Do you think this is reasonable, that somebody in my circumstances should only be paying 1 percent of their income in tax?'" Schoenberg said.

Sen. Orrin Hatch of Utah, the top Republican on the Senate Finance Committee, said he has a solution for rich people who want to pay more in taxes: Write a check to the IRS. There's nothing stopping you.

"There's still time before the filing deadline for them to give Uncle Sam some more money," Hatch said.

Schoenberg said Hatch's suggestion misses the point.

"This voluntary idea clearly represents a mindset that basically pretends there's no such things as collective goods that we produce," Schoenberg said. "Are you going to let people volunteer to build the road system? Are you going to let them volunteer to pay for education?"

The law is packed with tax breaks that help narrow special interests. But many of the biggest tax breaks benefit millions of American families at just about every income level, making them difficult for politicians to touch.

The vast majority of those who escape federal income taxes have low and medium incomes, and most of them pay other taxes, including Social Security and Medicare taxes, property taxes and retail sales taxes.

The share of people paying no federal income tax has dropped slightly the past two years. It was 47% for 2009. The main difference for 2010 was the expiration of a tax break that exempted the first $2,400 of unemployment benefits from taxation, Williams said.

"As a matter of policy, there would be a lot of ways to save money and actually make these things work better," said Leonard Burman, a public affairs professor at Syracuse University. "As a matter of politics, it's really, really difficult."

According to an analysis of 2009 tax data by the Joint Committee on Taxation, these are among the biggest tax breaks:

• 34.6 million taxpayers reduced their federal income taxes by a total of nearly $77 billion by deducting the interest they paid on their home mortgages.
• 36 million families saved more than $54 billion from the $1,000 per-child tax credit.
• 40.7 million taxpayers cut their federal income taxes by $40 billion by deducting state and local income, sales and personal property taxes.
• 33.5 million households cut their taxes by $21 billion by deducting state and local real estate taxes.
• 36 million families cut their taxes by nearly $35 billion by deducting charitable donations.
• 28 million taxpayers saved a total of $24 billion because their income from Social Security and railroad pensions was untaxed.
• 25.7 million low-income families collected a total of $55 billion from the earned income tax credit.

More from MSN Money:

• Tax day freebies
• Can't pay your taxes? File anyway
• Millions in tax credits went to people who didn't qualify
• 8 important tips for last-minute filers
• IRS increasing audits of the rich
• Who cheats on their taxes? Young, single men

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