NEW YORK (CNNMoney) -- The IRS defended itself this week against claims that the agency is going easy on the nation's super rich taxpayers.

According to a report by the Transactional Records Access Clearinghouse (TRAC) at Syracuse University, a non-profit research group, the task force the IRS created to examine the tax filings of the nation's wealthiest individuals has completed the audits of very few taxpayers.

Through a Freedom of Information Act order requesting performance statistics of the IRS's Global High Wealth Industry Group, the division that examines the tax filings of those with incomes or assets of $10 million or more, TRAC found that the agency has only completed 36 audits over the two and half years since the division's launch.

"This global high wealth initiative was rolled out to great fanfare as a huge game changer," said Susan Long, co-director of TRAC. "While it takes a while to gear up, it's now been more than two years into the program and the IRS has stopped talking about it, and despite the big fanfare, we have hardly anything to show for it."

IRS spokesman Terry Lemons, however, called the report's findings "misleading" and said that while the agency has completed 36 audits, there are currently more than 500 taxpayers being audited and "hundreds more audits in the early planning stages."

Lemons also said the high wealth unit wasn't designed to audit all millionaires -- it was launched to enforce the compliance of individuals with income or assets of $10 million or more who are also reporting entities like privately-held companies, trusts or real estate investments.

Because these returns are much more complicated than a typical 1040 or W-2, they need to go through a more rigorous examination process than a traditional audit, he said. And it can take a long time for these audits to be completed because of their complexity.

"This unit is highly specialized and is looking at a very small subset of taxpayers engaged in very sophisticated tax techniques -- not people who simply have a lot of cash," said Lemons. "It's not unusual for audits to stretch beyond a year."

Only 8,274 taxpayers reported income of more than $10 million in 2009, according the most recent IRS data available. Based on this figure, the unit has completed audits of 0.4% of these high-income earners and is currently auditing 6% of this group.

Still, the division has brought in a sizable chunk of revenue. Enforcement taken through the agency's high wealth division has resulted in revenue of $47.7 million since the program began, TRAC found. Of the 36 audits conducted, 24 resulted in additional tax being owed, while 12 did not require any additional taxes to be paid.

And this doesn't include the traditional audits the IRS is conducting of super wealthy taxpayers outside of this division. Traditional audit methods include field examinations, where an agent meets the taxpayer in person, and correspondence audits, where the IRS sends a taxpayer a notice requesting additional information.

These audits have been increasing significantly among the nation's wealthiest taxpayers. The IRS reported earlier this year that audits of millionaires nearly doubled last year and said the odds of getting audited jumped to 30% for taxpayers earning income of $10 million or more.

"The [TRAC] report makes it sound like we're not doing much on millionaires, but we actually have a great deal going on with high income taxpayers, so we strongly dispute TRAC's assessment on this," said Lemons.

But Long said she is concerned that the reason audit rates for millionaires are rising is because the IRS isn't spending enough time on each audit.

She pointed out that 44% of the audits given to millionaires last year were "correspondence audits." On average, these audits only took 2.6 hours of an auditor's time to complete, according to TRAC.

For field audits, the average amount of time spent per millionaire audit has dropped 25% from 41.7 hours in 2007 to 31.4 hours last year, TRAC said. And this year, the average millionaire audit has taken only 15.6 hours.

Therefore, as the agency spends less time on each audit, it can conduct more of them and report higher audit rates of millionaires. But by failing to send more taxpayers to the high wealth unit for more thorough audits, the IRS may not be investing the time and resources necessary to produce the full amount of tax owed, Long said.

TRAC also noted the limited resources that the IRS has allocated to the high wealth division. TRAC found that the unit only has 101 agents assigned to it, compared to the average size of 1,012 of other groups within the IRS.

The IRS acknowledged it has "been under some severe budget restrictions." But given these "restrictions" and the fact that the program is still relatively new, Lemons said he thinks the division is "making good progress."

"These are some of the most sophisticated returns we have come across, so a lot of what we're seeing is new territory for us," he said. "We have deliberately been making sure we take a very methodical approach, and it's going to take some time to get everything aligned the way we want."