German consumer sentiment unexpectedly fell to its lowest level in five months going into April, a survey showed on Thursday, partly due to people's concerns that rising inflation will erode their purchasing power.The consumer sentiment indicator, published by the Nuremberg-based GfK institute and based on a survey of around 2,000 Germans, fell to 9.8 going into April. Economists polled by Reuters had on average expected the headline figure to remain unchanged at 10.0.GfK said people's economic expectations and propensity to buy picked up, while the third component of the index - personal income expectations - fell for the second month in a row."A rise in inflation in Germany and the resultant intensified concerns over income buying power have obviously hindered full recovery of consumer sentiment," GfK researcher Rolf Buerkl said in a statement.Germany's inflation rate rose to 2.2 percent in February from 1.9 percent a month earlier, driven mainly by rising energy and food costs.