may 8 reuters  australias westpac banking corp wbcax on monday posted a 22 jump in firsthalf net profits as margins improved on the back of rising interest rates but warned tough mortgage competition will negatively impact margins going into the second half over the past year aggressive monetary tightening boosted banks earnings and margins however that could come to an end as inflation softening home prices and a cooling economy pose risks to credit growth and asset quality credit growth – both housing and business – will ease intense mortgage competition is expected to negatively impact industry and westpac’s margins in the next half it said the countrys no3 lender said net profit came in at a400 billion 270 billion for the six months ended march 31 compared with a328 billion a year earlier  net interest margin  the difference between interest earned from lending and paid for deposits  rose 5 basis points from a year earlier to 196 at the end of march westpac declared an interim dividend of 70 australian cents per share as compared with 61 australian cents last year 1  14819 australian dollars