Macquarie Bank will catch up with the big banks and make use of a covered bond program to help fund its A$27 billion mortgage book. The bank is a couple of years behind the major domestic Australian banks in making use of the funding method.Several credit ratings agencies over the weekend published opinions on a $1.98 billion cover pool, part of a notional $5 billion program.The profile of the cover pool provides some insight of the bank's business mix in the home loan segment.The average loan balance Moody's Investors Service put at $518,000. Moody's said 31 per cent of loans were investment loans while 48 per cent were granted on an interest-only basis or lines of credit.