The government on Monday raised interest rates on post office-operated small savings like Monthly Income Scheme (MIS) and Public Provident Fund (PPF) by up to 0.5 per cent. The objective is to make them more attractive to investors. An official release said interest rates on time deposits of one and two years have been increased by 0.5 per cent each to 8.2 per cent and 8.3 per cent. Rates for popular MIS has been hiked by 0.3 per cent to 8.5 per cent. Interest rate on PPF has been increased by 0.2 per cent to 8.8 per cent. The new rates will be effective from April 1, 2012 and will remain valid during 2012-13. There has been no change in the savings deposit rate which has been retained at 4 per cent.