...The 'A' IDR reflects SDUSD's 'bbb' financial resilience, 'Weakest' demographic trends and long-term liability burden, offset by 'Midrange' demographic and economic levels. The 'AAA' unlimited tax GO bond rating reflects the bonds' legal structure, warranting a rating of up to five notches above the district's IDR. The 'AAA' GO bond rating further reflects SDUSD's large, growing and diverse tax base....