Consumer inflation stood at 3.77 per cent in September, as against 3.69 per cent in the previous month, the government said on Friday. The pickup in inflation was driven by higher prices of food and fuel along with prevailing weakness in the rupee. The retail inflation figure was lower than economists' estimates. Analysts polled by news agency Reuters had forecast September's annual increase in the consumer price index at 4.0 per cent. Friday's data showed retail inflation - determined by the Consumer Price Index (CPI) - was within the Reserve Bank of India's (RBI) medium-term target of 4 per cent.