Standard&Poor's Rating Services affirmed its 'AA+/A-1+' rating on Michigan State Housing Development Authority's (MSHDA) rental housing revenue bonds series 2007F. The long-term component of the rating reflects the rating on MSHDA's single-family mortgage revenue bond resolution (AA+). The short-term component of the rating reflects the rating on a standby bond purchase agreement (SBPA) provided by The Bank of Nova Scotia (AA-/A-1+). The authority anticipates the current SBPA will be replaced by a substitute SBPA provided by PNC Bank National Association (A/A-1) on Oct. 17, 2012, the effective date. At that time, we expect the short-term component of the rating to reflect the short-term component of the rating on PNC Bank National Association; the long-term component of the rating