It's difficult to fathom ASB Bank's current strategy in the mortgage market.
What it looks like from the outside is that it decided to shut up shop for half of last year.
ASB's first-half results posted earlier this week showed its on-balance-sheet mortgage book is shrinking at an accelerating rate.
It was $518 million smaller at $75.51 billion at Dec 31 than it was at June 30 last year.
In November, the Reserve Bank's bank financial strength dashboard showed ASB's mortgage book shrank by $152.2 million in the September quarter, so that shrinkage increased to $365.5 million in the December quarter.
That followed growth of $674 million between Dec 31, 2022 and June 30, 2023 and growth of $1.35 billion in the previous first-half between June 30, 2022 and Dec 31, 2022.