LONDON--(BUSINESS WIRE)--A.M. Best has assigned a financial strength rating of A- (Excellent) and an issuer credit rating of ‘a-’ to Solunion Seguros de Crédito, Compañía Internacional de Seguros y Reaseguros S.A. (Solunion) (Spain). The outlook assigned to both ratings is stable. Solunion is the operating holding company of the Solunion group of companies, a 50/50 joint venture established in 2013 between MAPFRE GLOBAL RISKS, Compania Internacional de Seguros y Reaseguros S.A. (Spain), a wholl