The gauge has fallen 4.8 percent from a level of 450.15 on Aug. 9, before the Federal Reserve said it would buy $40 billion of mortgage debt a month until it sees improvement in the economy, the European Central Bank said it would buy bonds of indebted members that ask for aid and the Bank of Japan boosted its asset-purchase fund to 55 trillion yen ($693.4 billion). Photographer: Andrew Harrer/Bloomberg