The BSE benchmark index Sensex was trading 113 points down at 16,800 points a shortwhile ago. It fell by 59 points in early trade today as investors booked profits after yesterday's gains. The 30-share index had gained 82 points in the yesterday's highly volatile session.Similarly, the wide-based National Stock Exchange index Nifty was also trading 33 points down at 5,082 points a shortwhile ago. It declined by 13 points to 5,102 points in the opening trade.