The Sensex at the Bombay Stock Exchange ended with a slim gain of 20 points, or 0.1 per cent, at 15,936, after extremely volatile trade, on Monday. Late buying, on a better GDP growth forecast by the government helped the market recover from early losses. The Nifty at the National Stock Exchange rose 3 points, or 0.1 percent, to 4,760. However, stock markets in Japan, China, Hong Kong and South Korea lost between 0.3 per cent and 1 per cent.