For most retailers (except Macy's), 2010 was a year to forget. But there was one bright spot: "single-price" discount stores, which sell nearly every item on the shelves for a dollar or less. Sasser's 3,900-plus Dollar Tree stores posted record revenues and profits last year as the recession pushed people to seek out better and better deals. Sasser took advantage of the windfall by buying Canada's Dollar Giant chain, the company's first foray outside the U.S.
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