S&P Global Ratings raised its issuer credit rating (ICR) on Alameda-Contra Costa Transit District (AC Transit or the district), Calif., and its long-term rating on the district's series 2019 refunding certificates of participation (COPs) to 'AA+' from 'AA'. The upgrade reflects our view of AC Transit's improved debt service coverage (DSC) and debt and liabilities capacity, supported by tax revenue growth that has outpaced farebox declines, and our expectation that the district will maintain financial metrics supportive of a very strong financial risk profile. The outlook is stable. The COPs represent an interest in lease payments made by the district, as lessee, to the nonprofit AC Transit Financing Corp., as lessor, for the use and possession of the various leased