Not surprisingly, among the least profitable categories were two directly tied to the still-lagging real estate market: stores selling lawn and garden equipment and supplies, and building material and supplies dealers.

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An analysis of financial statements from privately held building material and supplies dealers (NAICS 4441) shows that sales are rebounding a little after three back-to-back years of declines between 2007 and 2009.

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After experiencing negative adjusted net profit margins in 2009, privately owned building-material and supplies dealers analyzed by Sageworks saw margins return to the black in 2010 and increase to between 2 and 3 percent in 2011.

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Before that I worked in the material balances department, where we had to match supplies and demands for different products.

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