The Sensex at the Bombay Stock Exchange fell 41 points, or 0.2 percent, to close, at 18,878,on monday, on profit-booking by funds amid a weak global trend. The Nifty of the National Stock Exchange shed 21 points, or 0.4 percent, to 5,699.In other Asian markets, China, Hong Kong, South Korea and Singapore fell between 0.7 percent and 3.7 percent.