NEW YORK (Standard&Poor's) Sept. 3, 2009--Standard&Poor's Ratings Services today corrected its rating on Michigan Higher Education Student Loan Authority's student loan revenue bonds series XII-N by raising the long-term rating on the bonds to 'AA' from 'A' (see list). The 'A' ratings were not previously raised to 'AA' due to an analytical process error. RELATED RESEARCH "Principles-Based Rating Methodology For Global Structured Finance Securities," published May 29, 2007; "Student Loan Criteria: Student Loan Programs," published Oct. 1, 2004; "Student Loan Criteria: The Rating Process For Student Loan Transactions," published Oct. 1, 2004; "Student Loan Criteria: Evaluating Risk In Student Loan Transactions," published Oct. 1, 2004; "Student Loan Criteria: Structural Elements In Student Loan Transactions," published Oct.