Wal-Mart, with nearly 6,000 stores in 13 countries and $309 billion in total 2004 sales, sits atop the heap of the world's top 30 grocers, reports www.planetretail.net. France-based retailer Carrefour was No. 2 at $113 billion in total sales, while Ahold, Metro and Tesco rounded out the top five, respectively. The London-based Tesco, with $68 billion in total 2004 sales, unseated Kroger Co. from the previous year's No.-5 position.