The BSE benchmark Sensex lost nearly 47 points in opening trade today. The 30-share Sensex, which has lost 793 points over the past five sessions, fell further by 46.64 points, or 0.28 percent, to 16,729.23 in opening trade, with capital goods, auto and IT stocks leading the fall.In a similar fashion, the wide-based National Stock Exchange Nifty index declined by 12.60 points, or 0.25 percent, to 5,017.85.