Standard&Poor's Ratings Services affirmed its 'BBB-' long-term rating on Advanced Technology Academy (ATA), Mich.'s series 2008 revenue bonds. The outlook is stable. The 'BBB-' rating reflects our view of the school's: Low financial reserves and minimal, albeit improved, liquidity in fiscal 2010 with 12 days' cash on hand; Reliance on the management company to run operations, particularly given that its founder and other administrators are also leaders and founders of the academy; and Inherent uncertainty associated with charter renewals, given that the final maturity of the bonds exceeds the time horizon of the existing charter. We believe these weaknesses are somewhat lessened by our view of the academy's: Generally positive operating results on a cash basis at levels