The Sensex at the Bombay Stock Exchange declined by 77 points in early trade today, due to selling by funds and speculators, as rupee slumped to a new all-time low, amid a weak trend at the Asian markets. The 30-share barometer had gained 12 points in yesterday's volatile session.The Nifty at the National Stock Exchange declined by 25 points to 5,853.In the Asian region, Hong Kong's Hang Seng index fell by 0.90 per cent, while Japan's Nikkei Index edged shed 0.82 per cent. The US Dow Jones Industrial Average ended 0.06 per cent lower yesterday.