Dah Sing Bank says its bottom-line earnings will be enhanced after it securitises US$300 million worth of residential mortgages. At a road show for what Dah Sing said was the largest asset securitisation deal originated in Asia outside Japan, financial controller Gary Wang said the deal represented about 20 per cent of its residential mortgage portfolio. After it, Dah Sing's exposure to home loans would fall from 45 per cent to less than 40 per cent. The sale also would bring a 0.5 per cent improvement to its capital adequacy ratio, which was 15 per cent in January. Mr Wang said the mortgage-backed notes would pay a coupon equivalent to the three-month London inter-bank offered rate, which stood at 5.91 per cent yesterday, plus a spread of less than 1 per cent. Considering the 9.8 per cent annual return the underlying mortgage pool was generating, this would enable Dah Sing to earn a net spread of about 3 per cent from the deal. This was near normal mortgage earnings, but if the sale proceeds were put in higher-yield assets, the deal would benefit earnings.