Global markets poised to log weakest quarterly performance in four years

An estimated $11tn wiped off value of world shares amid growing concerns over China's flagging economy

Global markets have suffered their worst quarterly performance since the depths of the eurozone crisis in 2011, with an estimated $11tn (7tn) wiped off the value of world shares, despite an attempted rebound on the last day of September.

After a summer of wild swings, sparked by growing fears of a slowdown in China, leading shares have slumped from the record highs of a few months earlier, and recorded their second quarterly decline in a row.