Alice Walton, left, and Jim Walton, chairman and chief executive officer of Arvest Bank Group Inc., smile during the Wal-Mart Stores Inc. annual shareholders meeting in Fayetteville, Arkansas, U.S., on Friday, June 7, 2013. Wal-Mart Stores Inc., which kicked off its annual meeting today, approved a new $15 billion share buyback program. Photographer: Sarah Bentham/Bloomberg via Getty Images