Maintaining the downward trend the Sensex at the Bombay Stock Exchange was trading down by 193 points to 16,840 in afternoon trade. Earlier the BSE benchmark Sensex fell by over 129 points to 16,903 in early trade today on fresh selling by funds and retail investors, triggered by weak global cues. The 30-share barometer, gained 326 points in last three sessions.Similarly the NSE 50-share Nifty also declined by 67 points to 5,098.