The New York Federal Reserve announced new leaders to its ranks on Thursday, among which included the manager of the central bank's balance sheet. This comes as the Fed has come under close scrutiny following a sharp surge in overnight funding rates in September that raised questions about U.S. monetary policymakers' ability to control its benchmark interest rate. Daleep Singh was named head of the markets group and Christopher Armstrong was named head of the financial services group. Lorie Logan was named manager of the System Open Market Account, the central bank's portfolio, a role which she had carried out since Simon Potter stepped down as head of the markets group in May. As part of her responsibilities, Logan will also oversee the Fed's repo operations.