NEW YORK--(BUSINESS WIRE)--Fitch Ratings has affirmed the following ratings for Martin County School Board, Florida (the district): --$33.1 million certificates of participation (COPs) at 'A'; --Implied general obligation at 'A+'. The Rating Outlook is revised to Stable from Negative. SECURITY The COPs are payable from lease rental payments made by the district, subject to annual appropriation, pursuant to a master lease purchase agreement. The district is required to appropriate funds for all