The top 100 Chinese real estate firms collectively registered a year-on-year growth of 33.2 percent in sales revenues last year to over 8.72 trillion yuan ($ 1.3 trillion), largely fueled by portfolio optimization and improved operational efficiency, according to a report released by the China Real Estate Top 10 Research Team on Tuesday.

The team is a joint program established by the Enterprise Research Institute of Development Research Center of the State Council of China, the Institute of Real Estate Studies of the Tsinghua University, and the property research institution China Index Academy.

As of the end of last year, the top 100 real estate developers took up 58.1 percent of the nation's market share, up 10.6 percent from the previous year, the report stated.

According to the research, the top 100 firms saw marked growth in both sales revenues and profits. Last year, the average revenues of these enterprises grew 27.3 percent year-on-year to 48.62 billion yuan and their net profits averaged 6.44 billion yuan, up 28.2 percent compared with the year before.

The report further revealed the rapid growth was due to the firms' efforts in optimizing their funding mix and enhancing operational efficiency.

Moreover, helped by tight regulation and deleveraging measures, the top enterprises also reduced financial risks. The average asset-liability ratio of the top 100 real estate developers stood at 77.8 percent last year, down 0.5 percent from the previous year.

Fulfilling social responsibilities was also high on the top firms' agenda. Leveraging financial, material and human resources, last year the property developers made great contributions to precise poverty alleviation, environmental protection and affordable housing projects, among others.

Li Jingya contributed to this story.