Health care and real estate dominate a list of the country’s 15 most profitable privately-held businesses, according to a report released Wednesday by Sageworks, a financial information company.

That heavy representation – nearly half the list – reflects the growth in those areas. Universal healthcare has spawned an influx of insured patients while the housing and office markets have rebounded from its recession-era doldrums.

Sagework’s rankings are based on the company profit margins over the 12 months ending in June. The calculations exclude taxes and include owner compensation in excess of their market-rate salaries.

Also featured heavily on the list are various service-based industry sectors like accounting and legal services, largely because of their consistent demand for their services combined with relatively low operating costs, according to Sageworks analyst Jenna Weaver. “These kinds of businesses sell services from bookkeeping to legal advice to health care and do not need to purchase as many, if any, physical goods,” Weaver said in a statement.

(Note: Profit margins of companies that made last year’s list have been revised since their initial release).