Erasing initial losses, the Sensex at the Bombay Stock Exchange was trading 91 points in the positive territory at 17,572 when reports last came in. The 30-share index, which had lost 324 points in the previous two sessions, dropped by 0.53 per cent, to 17,388 in the first few minutes of trade today.In a similar fashion, the wide-based National Stock Exchange Nifty index was trading 26 points in the green at 5,284 points