Each New York municipal and cooperative system purchasing power from the authority subject to contract provisions providing for regulation of resale rates by the authority, shall file an annual report in the form annexed hereto [Appendix 10-A, infra] with the authority within 90 days after the close of its fiscal years. Cooperative electric systems may, in lieu of filing the annual report in the form annexed hereto, file Rural Electrification Administration form and Rural Electrification Administration form 7a within 90 days after the close of their fiscal year.