Fitch Ratings-Barcelona/London-18 May 2012: Fitch Ratings has downgraded National Bank of Greece's, Efg Eurobank Ergasias', Alpha Bank's, Piraeus Bank's and Agricultural Bank of Greece's Long-term Issuer Default Ratings (IDR) and Support Rating Floors (SRF) to 'CCC' from 'B-' and Short-term IDRs to 'C' from 'B'. The Viability Rating (VR) of the five banks has been affirmed at 'f'. A full list of rating actions is at the end of this comment. The rating actions follow the downgrade of Greece's sovereign rating to 'CCC' from 'B-' (see "Fitch Takes Negative Rating Actions on Greece" dated 17 May 2012 on ... (full story)