...S&P Global Ratings assigned its '##+' long-term rating to Charleston, S.C.'s $25 million series 2022 installment purchase revenue bonds (IPRBs), and assign its '###' long-term rating to the city's series 2022 $9.63 million general obligation (GO) refunding bonds. At the same time, S&P Global Ratings affirmed its '###' long-term rating on Charleston's GO debt outstanding and its '##+' long-term rating on Charleston Public Facilities Corp., S.C.'s IPRBs outstanding, issued for the city. The outlook is stable. The city's full faith and credit pledge and its agreement to levy ad valorem property taxes, without l imitation as to rate or amount, secure the GO bonds. Bond proceeds will be used to refund the callable maturities of the city's 2014 GO bonds for net present value savings. Securing the corporation's IPRBs are installment purchase payments (or acquisition payments) from Charleston to cover annual debt service on the bonds, which are subject to annual appropriation by city council. In...