Many people think that the rich are able to weasel their way out of taxes, but they actually pay an overwhelming majority of the taxes in the United States.

What's more, their share of the tax burden is increasing.

The top 10 percent of taxpayers paid over 70% of the total amount collected in federal income taxes in 2010, the latest year figures are available, according to the Tax Foundation, a think tank that advocates for lower taxes. That's up from 55% in 1986.

The remaining 90% bore just under 30% of the tax burden. And 47% of all Americans pay hardly anything at all -- a fact that got Republican presidential candidate Mitt Romney into political hot water last year.

"There's been a huge myth created that the rich aren't paying anything," said William McBride, the Tax Foundation's chief economist. "The rich pay a much higher rate than the poor."

These numbers may not tell the whole story though.

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The tax code is getting more progressive, said Roberton Williams, a senior economist at the centrist Tax Policy Center. In 1986 there were just two tax rates -- 15% and 28%. Now there are seven income tax brackets, going from a low of 10% to a high of nearly 40%.

While taxes on investment income have declined a bit since 1986, incentives like child care and income tax credits for the poor have been greatly expanded.

But the rich are able to take advantage of tax breaks too. That's why Williams said there's a popular notion that the wealthy are somehow cheating the tax man. In fact, the Tax Policy Center found last year that there about 4,000 households with incomes over $1 million that were not paying anything at all.

Bob McIntyre, director of Citizens for Tax Justice, a liberal group, added that looking at just federal income taxes doesn't give the whole picture.

When factoring in state and local taxes, the top 10% pay just under half the tab. And when calculating tax burden as a percent of income, the tax code is even less progressive. The top 10% paid an average of 30% of their income in local, state, and federal taxes in 2011, said McIntyre. That's not much different than the 25% percent paid by the middle class.

"The system is a little progressive, but not much," McIntyre said.

Still, the wealthy are paying more taxes on a federal level simply because they are making so much more money. The top 10% of taxpayers take home 45% of the nation's income, according to Citizens for Tax Justice. Moreover, they seem to be getting richer all the time.

"The vast majority of income gains have gone to the people at the top," he said.

And it's this growing issue of income inequality that seems to anger people the most. Overall salaries and wages haven't even kept pace with inflation over the past few years.