(Sharecast News) - German investor sentiment deteriorated more than expected in October, according to a survey released on Tuesday by the ZEW Center for European Economic Research in Mannheim.

The ZEW economic expectations index fell to 28.1 from 34.7 in September, missing expectations for a reading of 29.9.

The current conditions index rose to -35.9 in October from -47.1 the month before.

ZEW President Achim Wambach said: "The German economy is slowly emerging from stagnation, but the recovery is not self-sustaining. Private consumption and investment remain weak because of high energy prices: They put real incomes under pressure, increase production costs and keep inflation higher for longer."