Rule 78. Budgets and other forecast records of estimated future income, receipts, and expenditures in connection with financing, construction, operations, acquisitions, disposals of properties, or investments by the company and its associate companies, including revisions of such estimates and memoranda that show reasons for the revisions, that are prepared for internal administrative or operating purposes and records that show a comparison of actual income, receipts, and expenditures with estimates shall be retained for a period of 3 years.
Mich. Admin. Code R. 460.2578