In recent years, several banks have colluded to manipulate LIBOR, benchmark rates that underpin trillions in assets worldwide. Now, Martin Wheatley–managing director of Britain's Financial Services Authority–is unveiling a plan to stop them from doing it again. Due to publish his agency's full review on Friday, Wheatley previewed a number of key changes on Thursday. It may become mandatory for more banks to provide quotes to LIBOR, he said, in order to curb the ability of a few banks to move the numbers. Wheatley also suggested basing rates on real trade data, rather than self-submitted estimates.