The BSE Sensex declined by 59 points in opening trade was trading down over by 126 to 18, 075 a short while ago.In a similar fashion, the wide-based National Stock Exchange index Nifty was trading 37 points to 5,494.In the Asian region, Hong Kong's Hang Seng index fell by 0.74 per cent, while Japan's Nikkei Index shed 0.26 per cent in morning trade. The US Dow Jones Industrial Average ended 0.76 per cent lower yesterday.