Confidence among some of the world’s business leaders has slumped to its lowest level since the third quarter of 2002, suffering from concerns about financial market volatility and mixed US economic data, according to an investment bank’s survey.

The Goldman Sachs Confidence Index – which was conducted in the last week of July and the first one of August – is based on chief executives’ assessments of business conditions for the coming quarter and regarded as a leading indicator of company sentiment.