Citigroup Inc. agreed to pay a penalty of almost 70 million rand to settle a South African antitrust investigation that said the U.S. bank participated in an alleged cartel to manipulate the value of the rand. “There could well be other settlements now that it seems the parties are prepared to come forward,” Patrice Rassou, head of equities at Sanlam Investment Management in Cape Town, said in an e-mailed response to questions on Monday.