Investor confidence in Germany rose unexpectedly sharply this month, a new survey showed on Tuesday, boosting expectations for a recovery in an economy -- the largest in the euro zone -- that was teetering on the edge of a new recession at the end of 2004. The ZEW economic research institute's economic expectations index, based on a poll of 318 analysts and institutional investors, rose by 9.0 points to plus 35.9 points in February, after already rising sharply the preceding month, ZEW said in a statement. It was the highest level since September 2004 and puts investor confidence back above its long-term average of plus 34.4 points. The ZEW barometer had already risen in January and the magnitude of the increase this month similarly caught analysts by surprise. Consensus forecasts had been for a more modest rise to around 30 points in the February index from 26.9 points in January. ZEW president Wolfgang Franz said: "A positive factor may have been the sharp increase in manufacturing orders in December. In particular, domestic demand for capital goods showed its biggest increase in more than 10 years, so that this can be seen as a signal for a noticeable improvement the domestic economy this year." The ZEW indicator represents the balance between positive and negative expectations for the economy over the next six months.