Citigroup CEO retires

Charles Prince’s four-year tenure as CEO of Citigroup Inc. ended yesterday, as the bank’s many challenges were left for now to interim CEO Sir Win Bischoff and Robert Rubin, who will become chairman. Citigroup, the largest bank in the country with $2.35 trillion in assets, announced massive write-offs in recent weeks, resulting in billions of dollars in credit losses. It will write off up to $11 billion to reflect the falling value of subprime-mortgage-related securities since September 30 — on top of the $2.2 billion in trading losses and mortgage-related write-downs announced on October 15.