Adjusted net profit margins were at a 10-year high average of about 6.5 percent in 2011, compared with nearly 5 percent in 2010.

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Private residential construction companies, including remodelers, posted an adjusted net profit margin of nearly 4 percent in 2011, following flat margins in 2010 and -1 percent margins in 2009, Sageworks data shows.

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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.

FORBES: Connect

Between 2004 and 2005, the adjusted net profit margin of the privately held oil and natural gas producers analyzed increased from 8.43 percent to 11.13 percent, which has been the recent peak in profitability for these companies.

FORBES: Oil Companies' Profits Track Gasoline Prices

Net profit margins are adjusted to exclude taxes and include owner compensation in excess of their market-rate salaries.

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Net profit margin has been adjusted to exclude taxes and include owner compensation in excess of their market-rate salaries.

FORBES: Gut check: Profitability up despite slowing sales growth

Net profit margin for the private companies has been adjusted to exclude taxes and include owner compensation in excess of their market-rate salaries.

FORBES: Comparing private, public company trends