OREANDA-NEWS. Fitch Ratings has affirmed the ratings for BNZ RMBS Trust Series 2008-1's Class A notes at 'AAAsf', Outlook Stable. The transaction is a securitisation of New Zealand conforming residential mortgages originated by Bank of New Zealand (BNZ, AA-/Stable/F1+). The rating action is as follows:

NZD 4,300m Class A notes affirmed at 'AAAsf'; Outlook Stable.

KEY RATING DRIVERS
The affirmation reflects Fitch's view that the available credit enhancement is sufficient to support the notes' current ratings, and the agency's expectations of New Zealand's economic conditions. The credit quality and performance of the loans in the collateral pool have also remained in line with expectations.

As of 31 January 2016, 30+ days arrears were very low at 0.07% of the underlying mortgage balance, and the transaction had no losses since closing.

The transaction remains within its 10-year revolving period, which ends in December 2018, and no amortisation of the notes has occurred to date. Fitch is comfortable with the long revolving period as the portfolio stratifications have not changed significantly since initial issue, BNZ's product mix has not materially changed over this time, and the portfolio is performing as expected.

RATING SENSITIVITIES
At Fitch's 'AAAsf' breakeven default rate of 6.4%, the Class A notes can withstand an additional 3.4% defaults at Fitch's 'AAAsf' loss severity.

DUE DILIGENCE USAGE
No third party due diligence was provided or reviewed in relation to this rating action.

DATA ADEQUACY
Fitch conducted a file review of 10 sample loan files focusing on the underwriting procedures conducted by BNZ compared to its credit policy at the time of underwriting. Fitch has checked the consistency and plausibility of the information and no material discrepancies were noted that would impact Fitch's rating analysis.

A comparison of the transaction's representations, warranties and enforcement mechanisms (RW&Es) to those of typical RW&Es for this asset class is available by accessing the reports and/or links under Related Research below.