German business confidence rose to its highest level in eight months in September, as companies felt increasingly satisfied with their current situation, a key survey showed on Tuesday. The widely watched business climate index, calculated monthly by the Ifo economic research institute, rose to 96.0 points in September from 94.6 points in August, Ifo said in a statement. It was the highest reading since January. The improvement in business sentiment in the eurozone's biggest economy took analysts by surprise -- consensus forecasts had predicted a slight deterioration in the September index. This month's reading did not fully take into account the Sept. 18 general election, the think-tank said. But "an evaluation of responses submitted before and after the vote showed a tendency to give more unfavourable responses after the election," which resulted in a hung parliament, Ifo said.