The Sensex at the Bombay Stock Exchange, which fell by over 90 points in opening trade today, stood at 73 points in the negative territory at 15,775 in afternoon trade.After losing 19 points in the previous session on Friday, the 30-share index fell further by 90 points in the first few minutes of trade today.In a similar fashion, the wide-based National Stock Exchange Nifty index was trading 18 points down at 4,729.In the Asia region, Hong Kong's Hang Seng index was down by 1.11 per cent, while the Tokyo Stock Exchange was closed. The US Dow Jones Industrial Average ended 0.45 per cent lower in the previous session.