Calamos Launches ETFs With Innovative Downside Protection Calamos Investments has introduced two new structured protection ETFs, CPSR and CPNM, offering 100% downside protection over a one-year outcome period. The CPSR ETF, tied to the S&P 500, features a 7.63% upside cap rate, while CPNM, linked to the Nasdaq-100, offers an 8.17% cap.1