The Sensex at the Bombay Stock Exchange declined 103 points, or 0.6 percent, to 17,816 in early trade, today, as funds and retail investors booked profits ahead of the RBI's monetary policy review. Later, after the apex bank's announcement, the Sensex lost further ground, and stood 254 points, or 1.4 percent in negative territory, at 17,664 in afternoon deals a short while ago. The 30-share Sensex had gained over 770 points in the past four trading sessions.