Today, the Illinois Association of Realtors (IAR) released a statement regarding the association’s erred Chicago median prices and home sales. The group admitted its data was incorrect yesterday, finding that their May statistics, as well as potentially years worth of data since 2008, was flawed.

The IAR says it is “investigating a technical error related to inconsistent data reporting affecting sales volume and media price reports for the city of Chicago.” The group added that only Chicago housing data has been impacted by the glitch, and that county and statewide reports are not being questioned.

“The one thing we do know is that this was an error and in no way intentional. But whatever the cause, this is absolutely unacceptable to us and we will take whatever is required to fix the problem or take other actions to ensure public confidence in our market reports,” said IAR in the statement.

“We regret any confusion in the marketplace that may have occurred due to this situation. We recognize that consumers have certainly been challenged to understand this market and our member Realtors are working hard every day to communicate the challenges of the marketplace to their clients,” the statement said.

Separately, NAR has also recently been accused of “overestimating the volume of existing home sales since 2007,” and the Chicago Tribune said that they will be releasing revised national home sales numbers dating back to 2008 in August, or the near future.