OREANDA-NEWS. Fitch Ratings has assigned a 'AAA' rating to DBS Bank Ltd.'s (DBS; AA-/Stable) Series 2015-1 USD1bn mortgage covered bond. The Outlook is Stable. The fixed-rate covered bond is due August 2018 and benefits from a 12 month extendable maturity which is triggered upon certain events. 

Under this programme, DBS can periodically issue up to USD10bn of bonds, which are secured by a dynamic pool of Singapore residential mortgage loans. 

KEY RATING DRIVERS
The 'AAA' rating is based on DBS's Long-Term Issuer Default Rating (IDR) of 'AA-', a Discontinuity Cap (D-Cap) of 3; and the asset percentage (AP) used in the programme's asset coverage test, which is equal to Fitch's breakeven AP for a 'AAA' rating of 85.5%. The Outlook on the covered bonds reflects the Stable Outlook on DBS's IDR.

Fitch takes only the AP used in the asset coverage test (85.5%) into account in its analysis, because the overcollateralization (OC) above the AP is secured by a demand loan back to the issuer that ranks senior in repayment to covered bond holders.

The 'AAA' breakeven AP of 85.5%, corresponding to a breakeven OC of 17%, is driven by the asset disposal loss of 19.0%, reflecting the maturity mismatches in the programme upon issuance and the refinancing assumptions applied to Singaporean residential mortgages. This is followed by the cover pool's credit loss of 4.2% in a 'AAA' scenario and finally the cash flow valuation component, which reduces the OC by 4.8% due to the excess spread under the programme, based on a stressed weighted average (WA) life of the assets versus the liabilities issued from the programme. The breakeven AP considers whether timely payments are met in a 'AA' scenario and tests for recoveries given default of at least 91% in a 'AAA' scenario.

The D-Cap of '3' reflects Fitch's "moderate high" discontinuity risk assessment related to the liquidity gap and systemic risk, systemic alternative management, and the cover pool-specific alternative management components. The D-Cap of 3 allows for a three-notch uplift above the issuer's IDR. In a scenario where the recourse of the covered bonds switches from the issuer to the cover pool, Fitch believes that a successful sale of the cover assets would be possible within the covered bond's extendible maturity of 12 months. 

No IDR uplift is applicable to the programme as the power to bail in creditors is not contemplated under the current resolution framework in Singapore. Therefore in Fitch's view, the IDR remains a satisfactory indicator of the likelihood that the recourse against the cover pool would be enforced.

Maturity mismatches in the programme are significant, with the WA residual life of the assets at 12.8 years and the liabilities at three years. At 9 July 2015, the cover pool consisted of 5,766 prime Singapore private residential mortgage loans equating to SGD4.5bn. The portfolio has a WA loan to value ratio (LVR) of 58.7% and is 42.7 months seasoned. By current balance, 37.5% of the loans in the pool are for investment purposes and 35.9% of the loans are held by non-Singaporeans (including borrowers with permanent residency and borrowers under Singapore's employment passes). The cover pool comprises loans secured by condominiums (75.9%), detached houses and other landed properties (11.3%), terrace houses (8.2%) and apartments (4.6%).

RATING SENSITIVITIES
The 'AAA' rating would be vulnerable to downgrade if any of the following occurred: (i) DBS's IDR was downgraded by three notches to 'A-'; (ii) the D-Cap fell by three categories to 0 (full discontinuity); or (iii) the AP that Fitch takes into account in its analysis increased above Fitch's 'AAA' breakeven AP of 85.5%.

Fitch's 'AAA' breakeven AP for the covered bond rating will be affected, among others, by the profile of the cover assets relative to outstanding covered bonds, which can change over time, even in the absence of new issuance. Therefore the 'AAA' breakeven AP to maintain the covered bond rating cannot be assumed to remain stable over time.