CME Group Inc. shed light on what could happen to the exchange giant's most-traded contracts—eurodollars, which permit bets on interest rates—if the scandal-plagued LIBOR benchmark they're tied to goes away in two years.

Officials at CME on Tuesday proposed a methodology for converting eurodollar futures and options to other derivatives at the exchange, ones linked to an alternative benchmark called the Secured Overnight Financing Rate, or SOFR. The plan could be tweaked based on customer feedback.

In 2021, the U.K. regulator that oversees LIBOR, the Financial Conduct Authority (FCA), will stop compelling banks to submit data used to calculate LIBOR. CME CEO Terry Duffy said in an October interview that the benchmark isn't guaranteed to go away then. But LIBOR is so deeply embedded in the global financial system that even a slim chance it disappears means contingency planning is necessary.