There are relevant documents. According to the document No.299 [2008] of Guoshuihan, the estimated profit rate is temporarily determined according to the following standards: 1. Non-indemnificatory housing development projects in urban and suburban areas where the people's governments of provinces, autonomous regions, municipalities directly under the Central Government and cities under separate state planning are located shall not be less than 20%; Located in prefecture-level cities, regions, leagues, states and suburbs, not less than15%; Located in other areas, not less than10%; Two, affordable housing development projects, affordable housing development projects in line with the Ministry of construction, the national development and Reform Commission, the Ministry of land and resources, China People's Bank on the issuance of the "notice" and other relevant provisions, not less than 3%.