S&P Global Ratings assigned its 'AAA/A-1+' dual rating to Iowa Finance Authority's(IFA) single-family mortgage bonds, 2020 series E (non-AMT, variable-rate, mortgage-backed securities, or MBS, program). The outlook is stable. The series 2020E bonds are being issued as variable-rate obligations and will receive enhancement in the form of a standby-bond purchase agreement (SBPA) from TD Bank N.A. The long-term component of the rating reflects our view of the authority's single-family MBS. The short-term component of the rating reflects our assessment of the liquidity facility in the form of an SBPA provided by TD Bank N.A., effective on Aug. 19, 2020. The SBPA will cover principal and 35 days' interests at a maximum 12% annual rate for the purchase price of bonds