The world’s wealthiest family just got US$11.6 billion richer.

Walmart Inc. reported its strongest sales in more than a decade Thursday, sending the retailer’s shares soaring as much 11 per cent and boosting the fortunes of Walton family members Alice, Jim, Rob, Lukas and Christy. Their collective net worth surged to US$163.2 billion as of 9:35 a.m. in New York, according to the Bloomberg Billionaires Index, a ranking of the world’s 500 richest people.

The gain erased their year-to-date losses.

Grocery sales at Walmart, the world’s biggest retailer, rose the most in nine years thanks to improved fresh-food offerings and higher online orders. The Bentonville, Arkansas-based company said comparable sales at U.S. Walmart stores rose 4.5 per cent in the quarter ended July 31, more than double analysts’ estimates. That provided a counterweight to an otherwise gloomy outlook for brick-and-mortar retail stores under threat from the likes of Whole Foods Markets owner Amazon.com Inc.

The Walton family’s fortune is primarily tied to Walmart shares. The clan owns about half of the retailer through Walton Family Holdings Trust and a holding company, Walton Enterprises.