Charges of construction enterprises include: \x0d\ (1) project sewage charges: refers to the project sewage charges paid by the construction site according to regulations. In the newly published Basis for Valuation of Construction Projects in Hebei Province, the project sewage charges have been included in the enterprise management fees. \x0d\ (2) Social security expenses. \x0d\ ① Old-age insurance premium: refers to the basic old-age insurance premium paid by enterprises for employees according to the prescribed standards. \x0d\ ② Unemployment insurance premium: refers to the unemployment insurance premium paid by enterprises for employees according to national standards. \x0d\ ③ Medical insurance premium: refers to the basic medical insurance premium paid by enterprises for employees according to the prescribed standards. \x0d\ ④ Maternity insurance premium: refers to the maternity insurance premium paid by the enterprise for employees according to the prescribed standards. \x0d\ ⑤ Work-related injury insurance premium (accidental injury insurance premium for dangerous operations): refers to the expenses paid by enterprises for accidental injuries of construction workers engaged in dangerous operations according to the provisions of the Construction Law. \x0d\ (3) Housing accumulation fund: refers to the housing accumulation fund paid by enterprises for employees according to the prescribed standards.