The BSE benchmark Sensex was trading 75 points up at 17,708 points in the noon trade a shortwhile ago. The 30-share barometer which gained 76 points yesterday, declined by nearly 21 points in early trade ahead of July inflation data amid profit-booking by speculators.The wide-based National Stock Exchange index Nifty was also trading 21 points up at 5,369 points, a shortwhile ago.