...S&P Global Ratings assigned its '###/A-1+' dual rating to Iowa Finance Authority's (IFA) single-family mortgage bonds, 2019 series B (non-AMT) (variable-rate) (mortgage-backed securities program [MBS]). The outlook is stable. The 2019 series B (series 2019B) bonds will be issued in conjunction with the 2019 series A and 2019 series C fixed-rate bonds, which S&P Global Ratings rated separately. Bond proceeds will be used to finance new mortgage loans under the FirstHome and Homes for Iowans programs through the purchase of MBS and to finance down payment assistance. The MBS will be guaranteed as to timely payment of principal and interest by the Government National Mortgage Assn. (Ginnie Mae), Fannie Mae, Federal Home Loan Mortgage Corp. (Freddie Mac); and backed by pools of mortgage loans insured by the Federal Housing Administration, guaranteed by the Veterans Administration or U.S. Department of Agriculture Rural Development, or insured by private mortgage insurance issued by an entity...