M Narendra, CMD of Indian Overseas Bank, says the net interest margin of the company for the first quarter was at 2.85, but going forward he hopes to maintain it to 3 per cent levels. During the period, IOB's operating profit rose by 73 per cent to Rs 802.60 crore from Rs 463.90 crore and the gross NPA stood at Rs 3,292 crore against Rs. 3,571 crore.