Apple is reportedly the fastest growing retailer in the U.S., according to retail sales expert David Berman. The company's first quarter sales are said to have grown to $4.6 billion, marking an 80% increase from the same period last year. "People don't realize how much money has been diverted to Apple." That increase accounted for one-fifth of all sales growth by publicly traded retailers in the U.S. In the Asia-Pacific region, sales rose 151% to $4.7 billion. After Apple, the biggest chunk of U.S. sales growth came from Amazon.com and Wal-Mart Stores.