DALLAS (CBSDFW.COM) – Dallas-based Dean Foods’ income tax rate was negative 38 percent last year.  It earned $126 million in profit.

Atmos Energy, also headquartered in Dallas, had an income tax rate of negative 22 percent.  Atmos earned $328 million in 2010.

And Chesapeake Energy, which has major operations in and around Fort Worth, had an income tax rate of negative 4 percent.   Chesapeake earned $2.8 billion in profit last year.

The numbers are revealed in a new report from Citizens for Tax Justice, a left-leaning nonprofit group.

The report, called “Corporate Taxpayers & Corporate Tax Dodgers, 2008-2010,” says 37 U.S. corporations paid no income tax in 2010.  Many actually got refund checks from the U.S. Treasury.

Officially, U.S. corporations are supposed to pay a 35 percent income tax rate.  In reality, according to the report, the average effective rate is about half that.

The study looked at 280 companies across the country for three years.  All are listed on the Fortune 500, and all were profitable during each of the three years.

The businesses which paid zero or negative income tax did so because of various loopholes and tax breaks.

In a statement, Chesapeake spokesman Michael Kehs said, “Agenda-driven uses of statistics don’t advance serious policy discussion or America’s search for jobs.  We paid over $650 million in taxes in 2010 and grew our workforce 25%, to more than 10,000 taxpaying Americans.  We invested 100% of our cash flow into finding and producing new sources of American energy, which helped lower the price of natural gas, saving consumers $250 million a day.  We are proud of our contributions to the country.”

Atmos spokesman Ray Granado emailed us a statement which read in part, “The period over which Citizens for Tax Justice and the Institute on Taxation and Economic Policy calculated the effective tax rate of -11.6% (Editor’s note: -11.6% was Atmos’ overall tax rate from 2008-2010) was a period that saw numerous economic incentive packages passed by Congress in response to the recent economic crisis. The enactment of economic stimulus measures was outside the control or influence of Atmos Energy. Like any responsible taxpayer, Atmos Energy has merely reported its taxes in accordance with the Internal Revenue Code.”

Neither company disputed the numbers in the report.

The study deals only with corporate income tax and not the other kinds of taxes that businesses pay.

It’s also important to note that several DFW-based companies paid much more in income tax.  Kimberly-Clark paid 24 percent; Exxon Mobil paid 13 percent; and Southwest Airlines paid 27 percent.  Texas Instruments paid the official rate of 35 percent last year.

Dean Foods has not responded to a request for comment.

The entire report is available here.