ASB Bank’s profit for the three months ended December rose to $144 million from $143 million in the same three months a year earlier, bringing its six months result to $238 million, down 10.9% on its previous first half.

Its charges for impaired loans jumped to $48 million in the latest three months from $19 million in the first quarter, bringing its six months charges to $67 million compared with just $5 million in the previous first half.

Of the first-half charges, $21 million relate to mortgages, $6 million to other retail loans and $40 million to business loans. ASB’s 90-day past due assets rose to $309 million at December 31, from $187 million at September 30, of which $198 million were mortgages, up from $111 million at September 30.

ASB’s on-balance sheet mortgages grew just $23 million to $36.43 billion in the three months ended December. Using Reserve Bank data from registered banks as a proxy for the market, ASB’s share of the mortgage market fell to 23.4% at December 31 from 23.75% three months earlier.

The market share loss was exacerbated by the $1.63 billion SBS Bank’s mortgage book being included for the first time – SBS gained its banking licence on October 7.

The Reserve Bank figures show total mortgage lending by registered banks grew $2.43 billion, including the SBS book, to $155.7 billion in the three months ended December.

ASB had a further $4.51 billion in off-balance sheet mortgages at December 31, down from $4.57 billion at September 30, which are generally loans approved but not drawn down.

The proportion of ASB’s mortgages with loan-to-value ratios (LVRs) above 80% rose to 16.9% at December 31 from 15.9% at September 30.

About 9.4% of its mortgages had lender’s mortgage insurance for the top 20% of each loan including 24.7% of those with LVRs above 90% and 21.7% of those with LVRs between 80.1% and 90%.