An Alabama hospital was given S&P Global's lowest bond rating of "D" on Wednesday, a day after it defaulted on bond interest payments. Jackson Hospital & Clinic in Montgomery defaulted on about $60 million worth of Medical Clinic Board of the City of Montgomery series 2015 bonds, which comprises 86% of the hospital's long-term debt, the S&P said in a statement explaining why it lowered the hospital's rating to "D" from "CC."