Market share of the Chinese top 100 real estate companies reached about 50 percent in 2017, up 7.9 percentage points year-on-year, suggesting a trend for concentration in the domestic property industry, report said.

Total sales of those companies grew 32.8 percent to surpass 6.37 trillion yuan ($1 trillion) last year, with a 23.7 percent increase in sales area, showing an overall positive performance, according to a report released Thursday by the China Index Academy, the Development Research Center of the State Council and Tsinghua University.

"Since 2003, the Chinese property industry has undergone a 15-year golden era as one of the pillar industries in the Chinese economy and an engine of urbanization," the report said.

Gross assets and sales of the top 100 real estate operators have seen fiftyfold growth amid the period, showing a steady and quick development, the report showed.

In 2017, those companies strengthened cost controls to improve the quality of operations, whose average revenue and net profit increased 28.5 percent and 30 percent respectively, it said.

They also helped to provide houses for low-income families and construct eco-friendly and energy-saving buildings, as part of the effort to realize corporate social responsibility, according to the report.

However, the average asset-liability ratio of the top 100 property developers reached 78.9 percent, up 2.2 percentage points over 2016, suggesting greater pressure from debt.

In the future, the report suggested those companies should not buy too many parcels of expensive land in hot cities to prevent the risk of overstock.

Besides, they need to attach more importance to the safety of cash flow to avoid capital risk, it said.