The BSE benchmark index Sensex declined by over 43 points in early trade today.The 30-share barometer, which had gained over 190 points in the previous two sessions, fell by 43.04 points, or 0.25 per cent, to 16,853.59 with stocks of oil and gas, metal, and banking sectors succumbing to profit-booking.Similarly, the wide-based National Stock Exchange index Nifty declined by 14.10 points, or 0.28 per cent, to 5,106.45.