The Sensex at the Bombay Stock Exchange was trading down by 46 points at 19,947 a short while ago as funds and retail investors booked profits amid a weak trend in the Asian region. It fell 18 points in early trade today.Similarly, the wide-based National Stock Exchange index Nifty, moved down by 17 points to 6,039.In the Asian region, Hong Kong's Hang Seng fell by 0.50 per cent, while Japan's Nikkei declined by 1.52 per cent in early trade today.In the US market, Dow Jones Industrial Average ended 0.20 per cent higher in yesterday's trade.