Food inflation fell sharply to a near four-year low of 1.81 per cent for the week ended December 10. Food inflation, as measured by Wholesale Price Index was 4.35 per cent in the previous week. It had stood at 13.22 per cent in the corresponding week of 2010. According to the official data released today, onions became cheaper by 49.38 per cent year-on-year during the week under review, while potato prices were down by 34.39 per cent. Prices of wheat also fell by 4.21 per cent. Overall, vegetables became cheaper by 26.37 per cent. However, other food products grew more expensive on an annual basis, led by protein-based items. Inflation in the overall primary articles category stood at 3.78 per cent during the week ended December 10, as against 5.48 per cent in the previous week. Primary articles have over 20 per cent weight in the wholesale price index.