The Sensex at the Bombay Stock Exchange closed 132 points, or 0.7 per cent lower, at 18,180, amid weak global bourses, today. The Nifty at the National Stock Exchange lost 43 points, or 0.8 per cent, to 5,462.Stock markets in Japan, China, Hong Kong and South Korea fell between 0.1 percent and 2 percent, as worries about a slowdown in global economic growth hurt investor sentiment.