CME Group is noticing increased demand for trading "higher-yield currencies" of Brazil, Russia, India and China, said Roger Rutherford, head of global foreign exchange. The exchange operator plans to capitalize on the interest by promoting the soundness of futures markets. "People are asking themselves, 'If I'm hedging my currency risk or other trading risk that involves the ruble, or possibly speculating in that currency, do I need to take that physical delivery of rubles?' " Rutherford said. "Why not just take the futures?"