Westpac says there has been a big drop in property investors since new loan-to-value ratio rules aimed at the amount of low-deposit mortgage lending came into play last year.
However, the bank's lending to first-home buyers was up by 12 per cent in 2017 compared with last year.
The bank said there was a big lift in first-home buyer (FHB) activity outside of Auckland, the Bay of Plenty, and Taranaki.
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"The majority of regions have secured the bulk of first-home buying, as high prices in Auckland continue to stifle FHBs from entering the market," the bank said in a commentary.