NEW YORK: Nineteen months after signing-up to PRISM, the acronymic retail measurement operation launched in 2006 by The Nielsen Company and the In-Store Marketing Institute, the planet's largest retailer has exited the Pioneering Research [for] In-Store Metrics program.

Wal-Mart always notoriously sensitive at releasing sales data to market research firms, set aside its reservations in May 2007 to sign-up to PRISM – then (and still) in its alpha stage.

However, the retail titan has now shied away from participating in this coming fall's launch of the national syndicated service .

It declined to explain its exit, although Nielsen glossed the loss, claiming: "Wal-mart was pleased with the insights it gleaned but has opted out of the syndicated service, consistent with its internal data sharing policies."

PRISM, hailed by Nielsen at its 2006 launch as heralding a "Golden Age of in-store marketing", measures consumer traffic in participating stores, aisle-by-aisle and category-by-category. 

Fifteen other major retail chains – among them A&P, Albertsons, Kroger, Meijer, Rite Aid, Safeway, Walgreens and Winn-Dixie – remain in the project. As do major marketers such as Coca-Cola, General Mills, Hewlett-Packard, Procter & Gamble, and Unilever.

Data sourced from; additional content by WARC staff