With respect to each employee to whom both sections 6 and 7(f) of the Act apply, the employer shall maintain and preserve payroll or other records containing all the information and data required by § 516.2(a) except paragraphs (a) (8) and (9), and, in addition, the following:

(a) Total weekly guaranteed earnings,

(b) Total weekly compensation in excess of weekly guaranty,

(c) A copy of the bona fide individual contract or the agreement made as a result of collective bargaining by representatives of employees, or where such contract or agreement is not in writing, a written memorandum summarizing its terms.