The corporate tax rate in the U.S. is 35%, but there aren't many companies that end up paying that amount. According to a study by the Citizens for Tax Justice and the Institute on Taxation and Economic Policy, the average tax rate of 280 S&P 500 companies investigated was 18.5% between 2008 and 2010.

Over 70 companies paid no taxes at all.

And then there were the 30 companies that paid less than nothing — we have those for you here.

But first, here's how they get away with it (from the report):

Accelerated depreciation: "The tax laws generally allow companies to write off their capital investments considerably faster than the assets actually wear out. This “accelerated depreciation” is technically a tax deferral, but so long as a company continues to invest, the tax deferral tends to be indefinite."

"The tax laws generally allow companies to write off their capital investments considerably faster than the assets actually wear out. This “accelerated depreciation” is technically a tax deferral, but so long as a company continues to invest, the tax deferral tends to be indefinite." Stock options: Most big corporations give their executives (and sometimes other employees) options to buy the company’s stock at a favorable price in the future. When those options are exercised, companies can take a tax deduction for the difference between what the employees pay for the stock and what it’s worth (while employees report this difference as taxable wages). Paying executives with options took off in the mid-1990s, in part because this kind of compensation was exempt from a law enacted in 1993 that tried to reduce income inequality by limiting corporate deductions for executive pay to $1 million per executive.

Most big corporations give their executives (and sometimes other employees) options to buy the company’s stock at a favorable price in the future. When those options are exercised, companies can take a tax deduction for the difference between what the employees pay for the stock and what it’s worth (while employees report this difference as taxable wages). Paying executives with options took off in the mid-1990s, in part because this kind of compensation was exempt from a law enacted in 1993 that tried to reduce income inequality by limiting corporate deductions for executive pay to $1 million per executive. Industry-specific tax breaks. The federal tax code also provides tax subsidies to companies that engage in certain activities.

The federal tax code also provides tax subsidies to companies that engage in certain activities. Offshore tax sheltering: Over the past decade or so, corporations and their accounting firms have become increasingly aggressive in seeking ways to shift their U.S. profits, on paper, into offshore tax havens, in order to avoid their U.S. tax obligations.

It's also worth pointing out two things: 2008-2009 were strange, anomalous years in corporate history due to the severity of the crisis AND these companies will all counter and say they paid tons of taxes that weren't necessarily income taxes.