<P> The 1990s saw an era of furious growth on an unprecedented scale and the incorporation of several new ideas and technology into the business . </P> <P> In 1990, US sales had quadrupled to $32 billion over the previous five years (4) and Walmart acquired The McLane Company, a food service distributor, which was later sold to Berkshire Hathaway in 2003 . </P> <P> In 1991, the company expanded into Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, and New York . Walmart expanded worldwide this year, with the opening of their first store outside the United States in Mexico City . They also acquired Western Merchandisers, Inc. of Amarillo, Texas . 1991 also saw the launch of the Sam's American Choice brand of products . </P> <P> On March 17, 1992 US President George H.W. Bush presented Sam Walton with the Presidential Medal of Freedom . Walton died on April 5, 1992 . His eldest son, S. Robson Walton, succeeded him as Chairman of the corporate board of directors, on April 7, 1992 . This year, Walmart had a presence in 45 states which by this time expanded into Idaho, Montana, and Oregon, as well as Puerto Rico . </P>

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