We expect the financial profile of the Dublin Airport Authority (DAA) to materially weaken from previous expectations because of significant declines in passenger traffic volumes. We are consequently lowering our assessment of DAA's stand-alone credit profile (SACP) to 'BBB' from 'A-'. Based on our opinion that the likelihood of extraordinary government support if needed is "moderate", we apply a one-notch uplift to DAA's SACP for extraordinary support. We are lowering the long-term corporate credit rating on DAA to 'BBB+' from 'A-' and the short-term rating to 'A-2' from 'A-1'. The negative outlook reflects our view that a recovery in traffic is uncertain at this stage, especially in the context of the current economic position of the Republic of Ireland, which