MikeMcD

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Both the media and public alike look forward to the release of the NPD Group's sales data each month, as it's one of the only unbiased glimpses we are given into the success of products in the games industry. And while the NPD has chosen to limit the amount of data it reveals publicly, big-name publishers like Electronic Arts and Activision are taking issue with NPD figures as a whole due to their omission of digital sales.
"Using NPD data for video game sales is like measuring music sales and ignoring something called iTunes," EA corporate communications executive Tiffany Steckler told CNN. "We see NPD's data as a misrepresentation of the entire industry."
NPD takes into account only new sales of physical games. So if you buy a copy of Burnout Paradise on the PlayStation Store, Team Fortress 2 on Steam, or Call of Duty maps on Xbox Live, that isn't taken into account when the NPD's numbers are released.

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