Today Barclays (BCS) , the U.K.-based global banking giant, and Time Inc. (TIME) , the parent of Fortune, announced that they had entered into an exclusive agreement for Barclays to develop a new family of stock indices based on the Fortune 500, the annual list of the largest companies in the U.S. ranked by revenue.

“We are thrilled to announce our agreement with Time Inc., through which Barclays will launch a unique and exciting set of indices based on the Fortune 500,” said Dupe Adeyemo, a director in EFS Solutions at Barclays. “The companies that comprise the Fortune 500 are some of the strongest, highest revenue generators in the U.S. and we believe that market participants will benefit from exposure to these companies through the investable indices that we are creating.”

Investors who buy in will be getting exposure to a huge slice of the U.S. market. The companies on the 2017 Fortune 500 list have a combined $12 trillion in revenues—a figure that’s equal to roughly two-thirds of U.S. GDP. Together they earned $890 billion in profits last year, have a total of $19 trillion in market value, and employ 28.2 million people worldwide.

Barclays’ new indices will track the performance of the public companies included in the list. The index family will include an equal weighted index and other weighting methodologies that will provide alternatives to market capitalization weighted indices. Barclays will initially launch the Barclays Fortune 500 Equal Weighted Index in July 2017.

For Time Inc, which owns brands such as Time, People, Sports Illustrated, and InStyle as well as Fortune, the agreement is the latest effort to unlock value from its venerable media properties. “The Fortune 500 list has always been a vital way to track the economy and we are pleased that Barclays has recognized the value of the franchise to create a new index,” said Alan Murray, Time Inc.’s Chief Content Officer and Fortune President. “At Time Inc., we are always looking for smart ways to enhance our brands and the Barclays Fortune 500 family of indices could not be a more natural extension for our iconic list that investors closely follow.”